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1.
Int J Cancer ; 150(1): 47-55, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34449869

RESUMO

Chronic inflammation has been associated with the development of lung cancer. In this study, we examined the association between C-reactive protein (CRP) and lung cancer in a prospective cohort study and used Mendelian randomization (MR) to clarify the causality. We included 420 977 participants from the UK Biobank (UKB) in the analyses; 1892 thereof were diagnosed with lung cancer during the follow-up. Hazards ratios (HRs) of CRP concentrations were estimated by Cox proportional hazard models and two approaches of MR analysis were performed. Besides, we added CRP concentrations to epidemiological model of lung cancer to evaluate its prediagnostic role through time-dependent receiver operating characteristic curve analysis. Elevated CRP levels were associated with a 22% increased lung cancer risk per 1 SD increase (HR = 1.22, 95% confidence interval [CI] = 1.18-1.26). Positive associations were observed in small cell lung cancer (HR = 1.21, 95% CI = 1.10-1.33), lung adenocarcinoma (HR = 1.17, 95% CI = 1.11-1.23) and lung squamous cell carcinoma (HR = 1.22, 95% CI = 1.14-1.31). No genetical association of circulating CRP levels and lung cancer risk was observed in MR analysis. When added to a risk model of lung cancer, CRP improved the performance of model as long as 8 years among current smokers (basic model: C-statistic = 0.78 [95% CI = 0.75-0.80]; CRP model: C-statistic = 0.79 [95% CI = 0.76-0.81]; Pnonadjusted  = .003, Padjusted  = .014). Our results did not support the causal association of circulating CRP with lung cancer risk. However, circulating CRP could be a prediagnostic marker of lung cancer as long as 8 years in advance for current smokers.

2.
J Ethnopharmacol ; 283: 114694, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34601084

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The flower buds of Tussilago farfara L. (Abbreviated as FTF) were widely used in traditional Chinese medicine (TCM) to treat respiratory diseases, including asthma, dry throat, great thirst, turbid saliva, stinky pus, and coughs caused by various causes. AIM OF STUDY: The aim of study is to explore the efficiency of FTF in vitro and in vivo for the treatment of lung inflammation, and to illustrate the possible mechanisms of FTF in treating inflammation-related respiratory diseases targeting NOD-like receptor 3 (NLRP3) inflammasome, nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear transcription factor-κB (NF-κB). METHODS: Lung inflammation model in vivo was induced by exposure of mice to cigarette smoke (CS) for two weeks. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), inflammatory factors, and histology in lung tissues were investigated in presence or absence of ethanol extract of the flower buds of T. farfara L. (FTF-EtOH). In the cell-based models, nitric oxide (NO) assay, flow cytometry assay, enzyme-linked immunosorbent assay (Elisa), and glutathione (GSH) assay were used to explore the anti-inflammatory and anti-oxidant effects of FTF-EtOH. Possible anti-inflammatory mechanisms of FTF targeting NLRP3 inflammasome, Nrf2, and NF-κB have been determined using western blot, quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR), immunofluorescence assay, nuclear and cytoplasmic extraction, and ubiqutination assay. RESULTS: FTF-EtOH suppressed CS-induced overproduction of inflammatory factors [e.g., tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß)], and upregulation of the content of intracellular MDA in the lung homogenate of mice. In cell-based models, FTF-EtOH reduced the lipopolysaccharide (LPS)-induced overproduction of inflammatory factors, and attenuated the CS extract-induced overgeneration of reactive oxygen species (ROS). Furthermore, FTF-EtOH up-regulated Nrf2 and its downstream genes through enhancing the stability of Nrf2 protein, and inhibited the activation of NF-κB and NLRP3 inflammasome, which have been confirmed by detecting the protein levels in the mouse model. CONCLUSIONS: FTF-EtOH effectively attenuated lung inflammation in vitro and in vivo. The protection of FTF-EtOH against inflammation was produced by activation of Nrf2 and inhibitions of NF-κB and NLRP3 inflammasome. These datas definitely support the ethnopharmacological use of FTF as an anti-inflammatory drug for treating respiratory diseases in TCM.

3.
Hum Exp Toxicol ; : 9603271211052991, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34752167

RESUMO

Background: Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step in the salvage pathway of mammalian nicotinamide adenine dinucleotide (NAD+) biosynthesis. Through its NAD+-biosynthetic activity, NAMPT is able to regulate the development of hepatic steatosis and inflammation induced by diet or alcohol. However, the roles NAMPT plays in the development of liver fibrosis remain obscure. Purpose: To investigate the roles of NAMPT-mediated NAD+ biosynthesis in hepatic stellate cell (HSC) activation and liver fibrosis. Research Design: Realtime RT-PCR and western blot analyses were performed to analyze the expression of profibrogenic genes. Sirius red staining was conducted to examine the fibrosis in liver. Mouse liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride (CCl4) 2 times a week for 6 weeks. Adenovirus-mediated NAMPT overexpression or nicotinamide mononucleotide (NMN) administration was carried out to study the effects of elevation of NAD+ levels on protecting CCl4-induced liver fibrosis in mice. LX2 cells or primary HSCs were used to study the role of NAMPT overexpression or NMN treatment in reducing profibrogenic gene expression in vitro. ResultsCCl4 administration suppresses NAMPT expression in liver and reduces hepatic NAD+ content. Tgfß1 treatment decreases intracellular NAD+ levels and NAMPT expression in LX2 cells. Adenovirus-mediated NAMPT overexpression augments liver NAD+ levels, inhibits HSC activation and alleviates CCl4-induced liver fibrosis in mice. Administration of NMN also suppresses HSC activation and protects against CCl4-induced liver fibrosis in mice. Conclusions: NAMPT-mediated NAD+ biosynthesis inhibits HSC activation and protects against CCl4-induced liver fibrosis.

4.
Small ; : e2104354, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766722

RESUMO

Water splitting is a promising sustainable technology to produce high purity hydrogen, but its commercial application remains a giant challenge due to the kinetically sluggish oxygen evolution reaction (OER). In this work, a time- and energy-saving approach to directly grow NiFe-layered double hydroxide (NiFe-LDH) nanosheets on nickel foam under ambient temperature and pressure is reported. These NiFe-LDH nanosheets are vertically rooted in nickel foam and interdigitated together to form a highly porous array, leading to numerous exposed active sites, reduced resistance of charge/mass transportation and enhanced mechanical stability. As self-supported electrocatalyst, the representative sample (NF@NiFe-LDH-1.5-4) shows an excellent large-current-density catalytic activity for OER in alkaline electrolyte, requiring low overpotentials of 190 and 220 mV to reach the current densities of 100 and 657 mA cm-2 with a Tafel slope of 38.1 mV dec-1 . In addition, NF@NiFe-LDH-1.5-4 as an overall water splitting electrocatalyst can stably achieve a large current density of 200 mA cm-2 over 300 h at a low cell voltage of 1.83 V, meeting the requirement of industrial hydrogen production. This exceedingly simple and ultrafast synthesis of low-cost and highly active large-current-density OER electrocatalysts can propel the commercialization of hydrogen producing technology via water splitting.

5.
Org Biomol Chem ; 19(43): 9369-9372, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757357

RESUMO

A unique C30 steroid, solitumergosterol A (1), was isolated from the deep-sea-derived fungus Penicillium solitum MCCC 3A00215. The planar structure and relative configuration of 1 were established mainly on the basis of extensive analysis of its 1D and 2D NMR as well as HRESIMS data, while its absolute configuration was clarified by comparison of the experimental and theoretical ECD spectra. Noteworthily, 1 is a Diels-Alder adduct of a heterogeneous steroid bearing a 6/6/6/6/5 pentacyclic carbon skeleton. Solitumergosterol A (1) exhibited weak in vitro anti-tumor activity against MB231 cells by a RXRα-dependent mechanism.

6.
Hepatology ; 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758510

RESUMO

BACKGROUND & AIMS: Interleukin (IL)-6 induced tumor progression has been well established via the induction of anti-apoptotic and proliferative genes. However, whether other mechanisms such as IL-6 regulation of circular RNAs (circRNAs) may also contribute to tumor development remains unknown. APPROACH & RESULTS: High-throughput RNA-seq was used to identify the differentially expressed circRNAs upon IL-6 stimulation in intrahepatic cholangiocarcinoma (ICC) cells. CircRNA GGNBP2 (derived from ggnbp2 gene, termed as cGGNBP2) was upregulated by IL-6 treatment in a time and concentration-dependent manner. The biogenesis of cGGNBP2 was regulated by RNA-binding protein DHX9, which was also mediated by IL-6 exposure. Mass spectrometry and western blotting identified a novel protein-cGGNBP2-184aa encoded by cGGNBP2. cGGNBP2-184aa promoted ICC cell proliferation and metastasis in vitro and in vivo. Mechanistically, cGGNBP2-184aa directly interacted with STAT3, phosphorylated STAT3Tyr705 , and played a positive regulatory role in modulating IL-6/STAT3 signaling. IL-6/cGGNBP2-184aa/STAT3 formed a positive feedback loop to sustain constitutive activation of IL-6/STAT3 signaling. Elevated cGGNBP2 expression was correlated with poor prognosis of ICC patients and was identified as an independent risk factor for patient prognosis. CONCLUSIONS: Our study demonstrates that cGGNBP2-184aa, a novel protein encoded by IL-6 induced cGGNBP2, formed a positive feedback loop to facilitate ICC progression and may serves as an auxiliary target for clinical IL-6/STAT3-targeting treatments in ICC.

7.
J Invest Dermatol ; 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34756880

RESUMO

Vulvar squamous cell carcinoma (VSCC) pathogenesis is traditionally defined by the presence or absence of human papillomavirus (HPV), but the definition of these groups and their molecular characteristics remains ambiguous across studies. Here, we present a retrospective cohort analysis of 36 patients with invasive VSCC where HPV status was determined using RNA in situ hybridization (ISH) and polymerase chain reaction (PCR). Clinical annotation, p16 immunohistochemistry (IHC), programmed death ligand-1 (PD-L1) IHC, HPV16 circular E7 RNA (circE7) detection, and RNA-sequencing (RNA-seq) of the cases was performed. A combination of ISH and PCR identified 20 cases (55.6%) as HPV-positive. HPV-status did not impact overall survival (HR: 1.36, 95% CI: 0.307 to 6.037, p=0.6857) or progression-free survival (HR: 1.12, 95% CI: 0.388 to 3.22, p=0.8367), and no significant clinical differences were found between the groups. PD-L1 expression did not correlate with HPV status, but increased expression of PD-L1 correlated with worse overall survival. Transcriptomic analyses (n=23) revealed distinct groups, defined by HPV status, with multiple differentially expressed genes previously implicated in HPV-induced cancers. HPV-positive tumors showed higher global expression of endogenous circular RNAs (circRNAs), including several circRNAs that have previously been implicated in the pathogenesis of other cancers.

8.
Sensors (Basel) ; 21(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770400

RESUMO

It is commonplace for people to perform various kinds of activities in groups. The recognition of human groups is of importance in many applications including crowd evacuation, teamwork coordination, and advertising. Existing group recognition approaches require snapshots of human trajectories, which is often impossible in the reality due to different data collection start time and frequency, and the inherent time deviations of devices. This study proposes an approach to synchronize the data of people for group recognition. All people's trajectory data are aligned by using data interpolating. The optimal interpolating points are computed based on our proposed error function. Moreover, the time deviations among devices are estimated and eliminated by message passing. A real-life data set is used to validate the effectiveness of the proposed approach. The results show that 97.7% accuracy of group recognition can be achieved. The approach proposed to deal with time deviations was also proven to lead to better performance compared to that of the existing approaches.


Assuntos
Reconhecimento Psicológico , Coleta de Dados , Humanos
9.
Am J Transl Res ; 13(10): 11899-11907, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34786120

RESUMO

OBJECTIVE: To observe the intervention effects of adjuvant pidotimod therapy on the serum inflammatory factor and GM-CSF and KL-6 expression levels in elderly mycoplasma pneumonia patients. METHODS: Elderly patients (n=104) diagnosed with mycoplasma pneumonia were divided into a control group (52 cases, given conventional anti-infective therapy combined with ambroxol) and a research group (52 cases, given conventional anti-infective therapy combined with ambroxol + pidotimod) according to the different treatment methods each patient was administered. The pulmonary function indexes (FVC, FEV1, FEV1/FVC), the serum inflammatory factor levels (interleukin (IL)-6, IL-8, the tumor necrosis factor α), the serum granulocyte-macrophage colony-stimulating factor (GM-CSF), and the Krebs von den Lungen-6 (KL-6) expression levels were measured before and after the treatment. The cough stopping times, the rale disappearance times, the hospital stay durations, the overall response rates, the incidences of adverse reactions during the administration, and the recurrence rates at 3, 6, and 12 months after the treatment were recorded. RESULTS: The research group had shorter cough stopping times, rale disappearance times, and hospital stays than the control group (all P<0.05). After the treatment, the FVC, FVE1, and FVE1/FVC levels in both groups were increased, and the research group had higher levels than the control group (all P<0.05). After the treatment, the serum tumor necrosis factor α, IL-6, IL-8, GM-CSF, and KL-6 levels in the two groups were significantly decreased, and the levels of these indicators in the research group were significantly lower than they were in the control group (all P<0.05). The total overall treatment response rate was higher, and the recurrence rate at 12 months after the treatment was significantly lower in the research group than they were in the control group (P<0.05). CONCLUSION: Adjuvant pidotimod therapy in the treatment of elderly patients with mycoplasma pneumonia can ameliorate patients' inflammatory responses and pulmonary functions, and reduce the serum GM-CSF and KL-6 factor levels, as well as the recurrence rate. Moreover, the combined medication is safe, and no significant increase in toxicity was found.

10.
Cell Rep ; 37(7): 110029, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34788618

RESUMO

Cooperation is common in nature and is pivotal to the development of human society. However, the details of how and why cooperation evolved remain poorly understood. Cross-species investigation of cooperation may help to elucidate the evolution of cooperative strategies. Thus, we design an automated cooperative behavioral paradigm and quantitatively examine the cooperative abilities and strategies of mice, rats, and tree shrews. We find that social communication plays a key role in the establishment of cooperation and that increased cooperative ability and a more efficient cooperative strategy emerge as a function of the evolutionary hierarchy of the tested species. Moreover, we demonstrate that single-unit activities in the orbitofrontal and prelimbic cortex in rats represent neural signals that may be used to distinguish between the cooperative and non-cooperative tasks, and such signals are distinct from the reward signals. Both signals may represent distinct components of the internal drive for cooperation.

11.
J Gastrointest Oncol ; 12(5): 1996-2003, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34790367

RESUMO

Background: As dendritic cells (DCs) are the major antigen-presenting cells of the immune system, understanding their role in esophageal cancer is essential for the development of preventative and treatment strategies. This study investigated the expression level and clinical value of tumor infiltrating dendritic cells (TIDCs) in tumor tissues of patients with esophageal cancer. Methods: From January 2019 to January 2021, 184 patients with esophageal cancer treated were prospectively enrolled as the observation group and 184 patients with benign esophageal tumors were selected as the control group. Tumor tissue samples were obtained and the expression level and phenotypes of the TIDCs were analyzed. The correlation between TIDC expression and clinical characteristics of patients with esophageal cancer was investigated. Results: The density of the TIDCs in the observation group was lower than that in the control group (8.76±2.25 vs. 9.97±2.19; P=0.000). Furthermore, the percentage of major histocompatibility complex-II (MHC-II) positive DCs and the percentage of CD54 positive DCs were relatively lower in the observation group compared to the control group (6.60%±2.12% vs. 9.34%±2.41%; P=0.000 and 7.41%±2.36% vs. 9.98%±2.47%; P=0.000, respectively). Esophageal cancer patients with lymph node metastasis had lower TIDC density, lower percentage of MHC-II positive DCs, and lower percentage of CD54 positive DCs compared to patients without node metastasis (P<0.05). Patients with stage III esophageal cancer also showed significantly lower TIDC density, lower percentage of MHC-II positive DCs, and lower percentage of CD54 positive DCs compared to patients with stage I/II esophageal cancer (P<0.05). Esophageal cancer patients with tumor diameter ≥4 cm presented with decreased TIDC density, decreased percentage of MHC-II positive DCs, and decreased percentage of CD54 positive DCs compared to patients with tumor diameter <4 cm (P<0.05). In addition, the density of TIDCs, the percentage of MHC-II positive DCs, and the percentage of CD54 positive DCs were significantly negatively correlated with the percentage of CD4+ T-lymphocytes and positively correlated with the percentage of CD8+ T-lymphocytes (P<0.05). Conclusions: Patients with esophageal cancer had low expression and function of TIDCs, and this was related to the imbalance of T-lymphocyte subsets, lymph node metastasis, TNM stage, and lesion size.

12.
Brain Res ; : 147711, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34793756

RESUMO

Traumatic brain injury (TBI) is a brain injury resulting from blunt mechanical external forces, which is a crucial public health and socioeconomic problem worldwide. TBI is one of the leading causes of death or disability. The primary injury of TBI is generally irreversible. Secondary injury caused by neuroinflammation could result in exacerbation of patients, which indicated that anti-inflammation and immunomodulatory were necessary for the treatment of TBI. Accumulated evidence reveals that the transplantation of umbilical cord mesenchymal stem cells (UCMSCs) could regulate the microenvironment in vivo and keep a balance of helper T 17(Th17)/ regulatory T cell (Treg). Therefore, it is reasonable to hypothesize that the UCMSCs could repair neurological impairment by maintaining the balance of Th17/Treg after TBI. In the study, we observed the phenomenon of trans-differentiation of T lymphocytes into Th17 cells after TBI. Rats were divided into Sham, TBI, and TBI+UCMSCs groups to explore the effects of the UCMSCs. The results manifested that trans-differentiating of Th17 into Treg was facilitated by UCMSCs, which was followed by promotion of neurological recovery and improvement of learning and memory in TBI rats. Furthermore, UCMSCs decreased the phosphorylation of nuclear factor-kappa B (NF-κB) and increased the expression of mothers against decapentaplegic homolog 3 (Smad3) in vivo and vitro experiments. In conclusion, UCMSCs maintained Th17/Treg balance via the transforming growth factor-ß (TGF-ß)/ Smad3/ NF-κB signaling pathway.

13.
BMC Cardiovasc Disord ; 21(1): 554, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34798829

RESUMO

BACKGROUND AND AIMS: Atherosclerosis is a vital cause of cardiovascular diseases. The correlation between proteinuria and atherosclerosis, however, has not been confirmed. This study aimed to assess whether there is a relationship between proteinuria and atherosclerosis. METHODS: From January 2016 to September 2020, 13,545 asymptomatic subjects from four centres in southern China underwent dipstick proteinuria testing and carotid atherosclerosis examination. Data on demography and past medical history were collected, and laboratory examinations were performed. The samples consisted of 7405 subjects (4875 males and 2530 females), excluding subjects failing to reach predefined standards and containing enough information. A multivariate logistic regression model was used to adjust the influence of traditional risk factors for atherosclerosis on the results. RESULTS: Compared with proteinuria-negative subjects, proteinuria-positive subjects had a higher prevalence rate of carotid atherosclerosis. The differences were statistically significant (22.6% vs. 26.7%, χ2 = 10.03, p = 0.002). After adjusting for common risk factors for atherosclerosis, age, sex, BMI, blood lipids, blood pressure, renal function, hypertensive disease, diabetes mellitus and hyperlipidaemia, proteinuria was an independent risk factor for atherosclerosis (OR = 1.191, 95% CI 1.015-1.398, p = 0.033). The Hosmer-Lemeshow test was used to test the risk prediction model of atherosclerosis, and the results showed that the model has high goodness of fit and strong independent variable prediction ability. CONCLUSIONS: Proteinuria is independently related to carotid atherosclerosis. With the increase in proteinuria level, the risk of carotid atherosclerotic plaque increases. For patients with positive proteinuria, further examination of atherosclerosis should not be ignored.

14.
Front Pharmacol ; 12: 756978, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803700

RESUMO

Inflammatory bowel disease (IBD) is characterized by chronic pathology associated with extensive intestinal microbial dysregulation and intestinal inflammation. Thus, efforts are underway to manipulate the gut microbiome to improve inflammatory pathology. Gegen Qinlian decoction (GQD), a traditional Chinese medicine prescription, has been widely utilized for treating diarrhea and ulcerative colitis (UC) for thousands of years. However, the underlying mechanism of its efficacy and whether its protective effect against colitis is mediated by the gut microbiota are poorly understood. In the present study, our data demonstrated that modified GQD (MGQD) administration significantly improved the pathological phenotypes and colonic inflammation challenged by DSS in mice, which were specifically manifested as reduced loss of body weight, shortening of colon length, DAI score, histological score and suppressed inflammatory response. 16S rRNA sequencing and targeted metabonomics analysis showed that MQGD altered the diversity and community landscape of the intestinal microbiota and the metabolic profiles. In particular, MQGD significantly boosted the abundance of the intestinal microbiota producing short-chain fatty acids (SCFAs), which are causally associated with promoting the development of Treg cells and suppressing the differentiation of pro-inflammatory Th17 cells. More importantly, transferring fecal microbiota from MGQD-treated or healthy controls exhibited equivalent alleviative effects on colitis mice. However, this protective effect could not be replicated in experiments of mice with depleted intestinal microbes through broad-spectrum antibiotic cocktails (ABX), further supporting the importance of SCFA-producing gut microbiota in the beneficial role of MGQD. In general, MGQD therapy has the potential to remodel the intestinal microbiome and reestablish immune homeostasis to ameliorate DSS-induced colitis.

15.
Dalton Trans ; 50(46): 17308-17318, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34787158

RESUMO

Polyoxometalate-based organic-inorganic hybrids have attracted considerable attention due to their fascinating structures and wide application prospects. In this work, using the same building blocks, ligands and metal ions (ZnW12O406-(ZnW12), 2,2'-bipyridine (2,2'-bipy), and Cu2+), we synthesized three new POM-based hybrids by controlling the pH values of the reaction systems. These three compounds {(Zn0.6(H2)0.4W12O40)[Cu(2,2'-bipy)(H2O)][Cu(2,2'-bipy)(H2O)2][Cu(2,2'-bipy)(H2O)3]}2·6H2O (1), (Me4N)2{ZnW12O40[Cu(2,2'-bipy)(H2O)][Cu(2,2'-bipy)(H2O)3]}·5H2O (2), and {(Zn0.5(H2)0.5W12O40)[Cu(2,2'-bipy)][Cu(2,2'-bipy)(H2O)][Cu(2,2'-bipy)(H2O)2]}·5H2O (3) have been structurally characterized by single-crystal X-ray diffraction. Compound 1 appears as a dimeric cluster structure, while compounds 2 and 3 appear as a 1D chain structure and a 2D network, respectively. The semiconducting properties of compounds 1-3 are different, which was demonstrated by band gap (Eg) and photocurrent response measurements. Compound 3 can efficiently catalyze the photooxidation of toluene to benzaldehyde with high selectivity using molecular oxygen as the oxidant component. Moreover, compound 3 was recycled and reused three times without significant degradation in conversion and selectivity. In addition, the mechanism of the photocatalytic reaction was also investigated.

16.
Ecotoxicol Environ Saf ; 228: 113011, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34837870

RESUMO

6:2 Chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA), an alternative product of perfluorooctane sulfonate (PFOS), has been frequently detected in various environmental, wildlife, and human samples. A few studies revealed the hepatotoxicity of 6:2 Cl-PFESA in animals, but the underlying toxicity mechanisms remain largely unknown. In this study, we investigated the lipid metabolism disorders of 6:2 Cl-PFESA through miRNA-gene interaction mode in Huh-7 cells. Our results showed that 6:2 Cl-PFESA significantly promoted cellular lipid accumulation and increased the expression of Acyl-CoA oxidase 1 (ACOX1), with the lowest effective concentrations (LOECs) of 3 µM. In silico analysis showed that hsa-miR-532-3p is a potential miRNA molecule targeting ACOX1. Fluorescent-based RNA electrophoretic mobility shift assay (FREMSA) and ACOX1-mediated luciferase reporter gene assays showed that hsa-miR-532-3p could directly bind to ACOX1 and inhibit its transcription activity. Besides, 6:2 Cl-PFESA decreased the expression of hsa-miR-532-3p in the PPARα-independent manner. Overexpression of hsa-miR-532-3p promoted 6:2 Cl-PFESA-induced cellular lipid accumulation and decreased the ACOX1 production in Huh-7 cells. Taken together, at human exposure relevant concentrations, 6:2 Cl-PFESA might upregulate the expression levels of ACOX1 through downregulating hsa-miR-532-3p, and disturbed lipid homeostasis in Huh-7 cells, which revealed a novel epigenetic mechanism of 6:2 Cl-PFESA-induced hepatic lipid toxic effects.

17.
Virus Evol ; 7(2): veab089, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804590

RESUMO

Ticks are important vector hosts of pathogens which cause human and animal diseases worldwide. Diverse viruses have been discovered in ticks; however, little is known about the ecological factors that affect the tick virome composition and evolution. Herein, we employed RNA sequencing to study the virome diversity of the Haemaphysalis longicornis and Rhipicephalus microplus ticks sampled in Hubei Province in China. Twelve RNA viruses with complete genomes were identified, which belonged to six viral families: Flaviviridae, Matonaviridae, Peribunyaviridae, Nairoviridae, Phenuiviridae, and Rhabdoviridae. These viruses showed great diversity in their genome organization and evolution, four of which were proposed to be novel species. The virome diversity and abundance of R. microplus ticks fed on cattle were evidently high. Further ecological analyses suggested that host species and feeding status may be key factors affecting the tick virome structure. This study described a number of novel viral species and variants from ticks and, more importantly, provided insights into the ecological factors shaping the virome structures of ticks, although it clearly warrants further investigation.

18.
iScience ; 24(11): 103332, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34805792

RESUMO

Deliberately optimizing the d-band position of an active component via electronic and lattice strain tuning is an effective way to boost its catalytic performance. We herein demonstrate this concept by constructing core-shell Au@NiPd nanoparticles with NiPd alloy shells of only three atomic layers through combining an Au catalysis with the galvanic replacement reaction. The Au core with larger electronegativity modulates the Pd electronic configuration, while the Ni atoms alloyed in the ultrathin shells neutralize the lattice stretching in Pd shells exerted by Au cores, equipping the active Pd metal with a favorable d-band position for electrochemical oxygen reduction reaction in an alkaline medium, for which core-shell Au@NiPd nanoparticles with a Ni/Pd atomic ratio of 3/7 exhibit a half-wave potential of 0.92 V, specific activity of 3.7 mA cm-2, and mass activity of 0.65 A mg-1 at 0.9 V, much better than most of the recently reported Pd-even Pt-based electrocatalysts.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34807821

RESUMO

A Piecewise Sub-Optimal Threshold (PSOT) is proposed to select the Most Significant Samples (MSS) of the Channel Impulse Response (CIR) for channel estimation of ultrasonic through-metal (UTM) communication. We analyze the correlation of echoes in the UTM channel, i.e., the periodicity and the exponential decay of echoes. The summation of mean-square error (MSE) is partitioned by using the periodicity of the echoes so that each partitioned MSE contains only one echo. The PSOT is derived by setting the first derivative of the partitioned MSE to zero. Channel tap energies, namely the received energies of ultrasonic waves, are required to calculate the PSOT, which can be estimated by using the exponential decay of echoes. After selecting MSSs by PSOT, we propose a further selection approach to get rid of possible noise samples in the MSS by using the correlation of echoes. Simulation results show that the proposed method is robust. Specifically, the performance of the proposed method does not depend on ultrasonic velocity, is unaffected by the estimated number of the echoes at a low signal-to-noise ratio (SNR), and can be applied to UTM channels with different metal thicknesses. The simulation also shows that the proposed method has a lower MSE than other methods, especially at low SNR.

20.
ACS Nano ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34808048

RESUMO

Developing affordable and efficient electrocatalysts as precious metal alternatives toward the hydrogen evolution reaction (HER) is crucially essential for the substantial progress of sustainable H2 energy-related technologies. The dual manipulation of coordination chemistry and geometric configuration for single-atom catalysts (SACs) has emerged as a powerful strategy to surmount the thermodynamic and kinetic dilemmas for high-efficiency electrocatalysis. We herein rationally designed N-doped multichannel carbon nanofibers supporting atomically dispersed Mo sites coordinated with C, N, and O triple components (labeled as Mo@NMCNFs hereafter) as a superior HER electrocatalyst. Systematic characterizations revealed that the local coordination microenvironment of Mo is determined to be a Mo-O1N1C2 moiety, which was theoretically probed to be the energetically favorable configuration for H intermediate adsorption by density functional theory calculations. Structurally, the multichannel porous carbon nanofibers with open ends could effectively enlarge the exposure of active sites, facilitate mass diffusion/charge transfer, and accelerate H2 release, leading to promoted reaction kinetics. Consequently, the optimized Mo@NMCNFs exhibited superior Pt-like HER performance in 0.5 M H2SO4 electrolyte with an overpotential of 66 mV at 10 mA cm-2, a Tafel slope of 48.9 mV dec-1, and excellent stability, outperforming a vast majority of the previously reported nonprecious HER electrocatalysts. The concept of both geometric and electronic engineering of SACs in this work may provide guidance for the design of high-efficiency molecule-like heterogeneous catalysts for a myriad of energy technologies.

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