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1.
Ecotoxicol Environ Saf ; 278: 116411, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38714085

RESUMO

Cadmium (Cd), a toxic element, often makes a serious threat to plant growth and development. Previous studies found that melatonin (Mel) reduced Cd accumulation and reestablished the redox balance to alleviate Cd stress in Medicago sativa L., however, the complex molecular mechanisms are still elusive. Here, comparative transcriptome analysis and biochemical experiments were conducted to explore the molecular mechanisms of Mel in enhancing Cd tolerance. Results showed that 7237 differentially expressed genes (DEGs) were regulated by Mel pretreatment to Cd stress compared to the control condition in roots of Medicago sativa L. Besides, in comparison with Cd stress alone, Mel upregulated 1081 DEGs, and downregulated 1085 DEGs. These DEGs were mainly involved in the transcription and translation of genes and folding, sorting and degradation of proteins, carbohydrate metabolism, and hormone signal network. Application of Mel regulated the expression of several genes encoding ribosomal protein and E3 ubiquitin-protein ligase involved in folding, sorting and degradation of proteins. Moreover, transcriptomic analyse suggested that Mel might regulate the expression of genes encoding pectin lyase, UDP-glucose dehydrogenase, sucrose-phosphate synthase, hexokinase-1, and protein phosphorylation in the sugar metabolism. Therefore, these could promote sucrose accumulation and subsequently alleviate the Cd damage. In conclusion, above findings provided the mining of important genes and molecular basis of Mel in mitigating Cd tolerance and genetic cultivation of Medicago sativa L.

2.
Blood ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657191

RESUMO

Hematopoietic differentiation is controlled by intrinsic regulators and the extrinsic hematopoietic niche. Activating transcription factor 4 (ATF4) plays a crucial role in the function of fetal and adult hematopoietic stem cell maintenance; however, the precise function of ATF4 in the bone marrow niche and the mechanism by which ATF4 regulates adult hematopoiesis remain largely unknown. Here, we employ four cell-type-specific mouse Cre lines to achieve conditional knockout of Atf4 in Cdh5+ endothelial cells, Prx1+ bone marrow stromal cells, Osx+ osteo-progenitor cells, and Mx1+ hematopoietic cells, and uncover the role of Atf4 in niche cells and hematopoiesis. Intriguingly, depletion of Atf4 in niche cells does not affect hematopoiesis; however, Atf4-deficient hematopoietic cells exhibit erythroid differentiation defects, leading to hypoplastic anemia. Mechanistically, ATF4 mediates direct regulation of Rps19bp1 transcription, which is, in turn, involved in 40S ribosomal subunit assembly to coordinate ribosome biogenesis and promote erythropoiesis. Finally, we demonstrate that under conditions of 5-fluorouracil-induced stress, Atf4 depletion impedes the recovery of hematopoietic lineages, which requires efficient ribosome biogenesis. Taken together, our findings highlight the indispensable role of the ATF4-RPS19BP1 axis in the regulation of erythropoiesis.

3.
Cell Commun Signal ; 22(1): 195, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539203

RESUMO

BACKGROUND: Lung cancer is cancer with the highest morbidity and mortality in the world and poses a serious threat to human health. Therefore, discovering new treatments is urgently needed to improve lung cancer prognosis. Small molecule inhibitors targeting the ubiquitin-proteasome system have achieved great success, in which deubiquitinase inhibitors have broad clinical applications. The deubiquitylase OTUD3 was reported to promote lung tumorigenesis by stabilizing oncoprotein GRP78, implying that inhibition of OTUD3 may be a therapeutic strategy for lung cancer. RESULTS: In this study, we identified a small molecule inhibitor of OTUD3, Rolapitant, by computer-aided virtual screening and biological experimental verification from FDA-approved drugs library. Rolapitant inhibited the proliferation of lung cancer cells by inhibiting deubiquitinating activity of OTUD3. Quantitative proteomic profiling indicated that Rolapitant significantly upregulated the expression of death receptor 5 (DR5). Rolapitant also promoted lung cancer cell apoptosis through upregulating cell surface expression of DR5 and enhanced TRAIL-induced apoptosis. Mechanistically, Rolapitant directly targeted the OTUD3-GRP78 axis to trigger endoplasmic reticulum (ER) stress-C/EBP homologous protein (CHOP)-DR5 signaling, sensitizing lung cancer cells to TRAIL-induced apoptosis. In the vivo assays, Rolapitant suppressed the growth of lung cancer xenografts in immunocompromised mice at suitable dosages without apparent toxicity. CONCLUSION: In summary, the present study identifies Rolapitant as a novel inhibitor of deubiquitinase OTUD3 and establishes that the OTUD3-GRP78 axis is a potential therapeutic target for lung cancer.


Assuntos
Chaperona BiP do Retículo Endoplasmático , Neoplasias Pulmonares , Compostos de Espiro , Humanos , Camundongos , Animais , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Proteômica , Proteases Específicas de Ubiquitina/metabolismo , Apoptose , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
4.
Front Psychol ; 15: 1364939, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440250

RESUMO

Microsaccades are small, involuntary eye movements that occur during fixation. Since the 1950s, researchers have conducted extensive research on the role of microsaccades in visual information processing, and found that they also play an important role in human advanced visual cognitive activities. Research over the past 20 years further suggested that there is a close relationship between microsaccades and visual attention, yet lacking a timely review. The current article aims to provide a state-of-the-art review and bring microsaccades studies into the sight of attention research. We firstly introduce basic characteristics about microsaccades, then summarized the empirical evidence supporting the view that microsaccades can reflect both external (perception) and internal (working memory) attention shifts. We finally conclude and highlight three promising avenues for future research.

5.
Curr Neurovasc Res ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38409728

RESUMO

Electroacupuncture (EA) treatment plays a protective role in cerebral ischemiareperfusion (CIR) injury. However, the underlying molecular mechanism is still not fully elucidated. METHODS: All rats were randomly divided into five groups: the SHAM group, MCAO group, MCAO+EA (MEA) group, MCAO+METTL3 overexpression+EA (METTL3) group and MCAO+lncRNA H19 overexpression+EA (lncRNA H19) group. The middle cerebral artery occlusion (MCAO) rats were established to mimic CIR injury. The overexpression of lncRNA H19 and METTL3 was induced by stereotactic injection of lentiviruses into the rat lateral ventricles. The rats in the MEA, METTL3, and lncRNA H19 groups were treated with EA therapy on "Renzhong" (DU26) and "Baihui" (DU20) acupoints (3.85/6.25Hz; 1mA). Besides, the neurological deficit scoring, cerebral infarction area, pathological changes in brain tissue, total RNA m6A level, and the expression of METTL3, S1PR2, TLR4, NLRP3 and lncRNA H19 were detected in this experiment. RESULTS: EA improved the neurological deficit scoring, cerebral infarction area, and pathological injury in MCAO rats, while these beneficial effects of EA on CIR injury were attenuated by the overexpression of METTL3 or lncRNA H19. More importantly, EA down-regulated the total RNA m6A level and the expression of METTL3, S1PR2, TLR4, NLRP3 and lncRNA H19 in MCAO rats. Instead, the overexpression of METTL3 or lncRNA H19 was found to reverse the EA-induced down-regulation. CONCLUSION: The findings indicated that EA might down-regulate the S1PR2/TLR4/NLRP3 signaling pathway via m6A methylation of lncRNA H19 to alleviate CIR injury. Our findings provide a new insight into the molecular mechanism of EA on CIR injury.

6.
PLoS Pathog ; 19(11): e1011589, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37934791

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to evolve throughout the coronavirus disease-19 (COVID-19) pandemic, giving rise to multiple variants of concern (VOCs) with different biological properties. As the pandemic progresses, it will be essential to test in near real time the potential of any new emerging variant to cause severe disease. BA.1 (Omicron) was shown to be attenuated compared to the previous VOCs like Delta, but it is possible that newly emerging variants may regain a virulent phenotype. Hamsters have been proven to be an exceedingly good model for SARS-CoV-2 pathogenesis. Here, we aimed to develop robust quantitative pipelines to assess the virulence of SARS-CoV-2 variants in hamsters. We used various approaches including RNAseq, RNA in situ hybridization, immunohistochemistry, and digital pathology, including software assisted whole section imaging and downstream automatic analyses enhanced by machine learning, to develop methods to assess and quantify virus-induced pulmonary lesions in an unbiased manner. Initially, we used Delta and Omicron to develop our experimental pipelines. We then assessed the virulence of recent Omicron sub-lineages including BA.5, XBB, BQ.1.18, BA.2, BA.2.75 and EG.5.1. We show that in experimentally infected hamsters, accurate quantification of alveolar epithelial hyperplasia and macrophage infiltrates represent robust markers for assessing the extent of virus-induced pulmonary pathology, and hence virus virulence. In addition, using these pipelines, we could reveal how some Omicron sub-lineages (e.g., BA.2.75 and EG.5.1) have regained virulence compared to the original BA.1. Finally, to maximise the utility of the digital pathology pipelines reported in our study, we developed an online repository containing representative whole organ histopathology sections that can be visualised at variable magnifications (https://covid-atlas.cvr.gla.ac.uk). Overall, this pipeline can provide unbiased and invaluable data for rapidly assessing newly emerging variants and their potential to cause severe disease.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , SARS-CoV-2/genética , Virulência , Aprendizado de Máquina
7.
Funct Integr Genomics ; 23(3): 290, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37658940

RESUMO

Clk4-associated serine/arginine-rich protein (CLASRP), an alternative splicing regulator, may be involved in the development and progression of cancer by regulating the activity of the CDC-like kinase (Clk) family. This study explored the biological function of CLASRP in colorectal cancer (CRC). The expression of CLASRP, which is associated with clinicopathological features, was analysed in CRC tissues and paired noncancer tissues by RT-PCR. The roles of CLASRP were investigated in CRC cells transfected with plasmids or shRNA through proliferation, migration and invasion assays in vitro and a xenograft model in vivo. Apoptosis was analysed using CLASRP-overexpressing CRC cells by western blotting. Clk inhibitors were used to perform functional research on CLASRP in CLASRP-overexpressing CRC cells. CLASRP was significantly upregulated in CRC cell lines, while high CLASRP expression was correlated with metastasis in CRC patients. Functionally, overexpression of CLASRP significantly promoted the proliferation, migration and invasion of CRC cells in vitro and tumour growth in vivo. Mechanistically, the proliferation, migration and invasion of CLASRP-overexpressing CRC cells were inhibited by Clk inhibitors, accompanied by low expression of CLASRP at the gene and protein levels. Clk inhibitors induced apoptosis of CLASRP-overexpressing CRC cells, resulting in direct blockade of cell growth. The expression levels of cleaved caspase 3 and cleaved caspase 8 were increased in CLASRP-overexpressing CRC cells treated with Clk inhibitors. CLASRP might serve as a promotional oncogene in CRC cells and be suppressed by Clk inhibitors through activation of caspase pathways.


Assuntos
Neoplasias Colorretais , Oncogenes , Humanos , Apoptose , Processamento Alternativo , Linhagem Celular , Neoplasias Colorretais/genética , Fatores de Processamento de Serina-Arginina
8.
Cell Death Dis ; 14(9): 611, 2023 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-37716979

RESUMO

Development of colorectal cancer (CRC) involves activation of Kirsten rat sarcoma viral oncogene homolog (KRAS) signaling. However, the post-transcriptional regulation of KRAS has yet to be fully characterized. Here, we found that the colorectal neoplasia differentially expressed (CRNDE)/heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1) axis was notably elevated in CRC and was strongly associated with poor prognosis of patients, while also significantly promoting CRC cell proliferation and metastasis both in vitro and in vivo. Furthermore, CRNDE maintained the stability of hnRNPA2B1 protein by inhibiting E3 ubiquitin ligase TRIM21 mediated K63 ubiquitination-dependent protein degradation. CRNDE/hnRNPA2B1 axis facilitated the nuclear export and translation of KRAS mRNA, which specifically activated the MAPK signaling pathway, eventually accelerating the malignant progression of CRC. Our findings provided insight into the regulatory network for stable hnRNPA2B1 protein expression, and the molecular mechanisms by which the CRNDE/hnRNPA2B1 axis mediated KRAS nucleocytoplasmic transport and translation, deeply underscoring the bright future of hnRNPA2B1 as a promising biomarker and therapeutic target for CRC. By hindering hnRNPA2B1 from binding to the E3 ubiquitin ligase TRIM21, whose mediated ubiquitin-dependent degradation was thereby inhibited, CRNDE protected the stability of hnRNPA2B1's high protein expression in CRC. Supported by the high level of the oncogenic molecule CRNDE, hnRNPA2B1 bound to KRAS mRNA and promoted KRAS mRNA nucleus export to enter the ribosomal translation program, subsequently activating the MAPK signaling pathway and ultimately accelerating the malignant progression of CRC.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Transporte Ativo do Núcleo Celular , Proteínas Proto-Oncogênicas p21(ras)/genética , Proliferação de Células/genética , Sistema de Sinalização das MAP Quinases , Neoplasias Colorretais/genética
9.
Inorg Chem ; 62(33): 13615-13625, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37549013

RESUMO

For photocatalytic CO2 reduction to produce syngas, there are challenges in achieving a high catalytic efficiency and precise control over the product ratio. In this study, two non-noble metal complexes Cobpy and Cubpy (bpy = 2,2'-bipyridine) as cocatalysts for CO2 reduction and hydrogen evolution, respectively, were in situ supported on carbon nitride hollow nanospheres to construct a hybrid system for photocatalytic syngas production. The resulting CO/H2 ratio can be precisely regulated within a wide range of 0:1-9:1 by accurately controlling the content of the two complexes. The presence of the two complexes promotes the migration of photogenerated electrons of the carbon nitride. CO2 can be reduced to CO on the photoreduced species Co(bpy)2+ of Cobpy on CNHS, and H+ can be reduced to H2 on the photoreduced species Cu(bpy)2+ of Cubpy. Furthermore, this method is also applicable to other photocatalysts, such as CdS and TiO2 for generating syngas and regulating product ratios.

10.
EMBO J ; 42(16): e110757, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37427448

RESUMO

The tumor microenvironment (TME) directly determines patients' outcomes and therapeutic efficiencies. An in-depth understanding of the TME is required to improve the prognosis of patients with cervical cancer (CC). This study conducted single-cell RNA and TCR sequencing of six-paired tumors and adjacent normal tissues to map the CC immune landscape. T and NK cells were highly enriched in the tumor area and transitioned from cytotoxic to exhaustion phenotypes. Our analyses suggest that cytotoxic large-clone T cells are critical effectors in the antitumor response. This study also revealed tumor-specific germinal center B cells associated with tertiary lymphoid structures. A high-germinal center B cell proportion in patients with CC is predictive of improved clinical outcomes and is associated with elevated hormonal immune responses. We depicted an immune-excluded stromal landscape and established a joint model of tumor and stromal cells to predict CC patients' prognosis. The study revealed tumor ecosystem subsets linked to antitumor response or prognosis in the TME and provides information for future combinational immunotherapy.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Microambiente Tumoral , Ecossistema , Células Matadoras Naturais , Imunoterapia
11.
Nature ; 619(7969): 338-347, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380775

RESUMO

Spillover events of avian influenza A viruses (IAVs) to humans could represent the first step in a future pandemic1. Several factors that limit the transmission and replication of avian IAVs in mammals have been identified. There are several gaps in our understanding to predict which virus lineages are more likely to cross the species barrier and cause disease in humans1. Here, we identified human BTN3A3 (butyrophilin subfamily 3 member A3)2 as a potent inhibitor of avian IAVs but not human IAVs. We determined that BTN3A3 is expressed in human airways and its antiviral activity evolved in primates. We show that BTN3A3 restriction acts primarily at the early stages of the virus life cycle by inhibiting avian IAV RNA replication. We identified residue 313 in the viral nucleoprotein (NP) as the genetic determinant of BTN3A3 sensitivity (313F or, rarely, 313L in avian viruses) or evasion (313Y or 313V in human viruses). However, avian IAV serotypes, such as H7 and H9, that spilled over into humans also evade BTN3A3 restriction. In these cases, BTN3A3 evasion is due to substitutions (N, H or Q) in NP residue 52 that is adjacent to residue 313 in the NP structure3. Thus, sensitivity or resistance to BTN3A3 is another factor to consider in the risk assessment of the zoonotic potential of avian influenza viruses.


Assuntos
Aves , Interações entre Hospedeiro e Microrganismos , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Zoonoses Virais , Animais , Humanos , Aves/virologia , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/transmissão , Influenza Aviária/virologia , Influenza Humana/prevenção & controle , Influenza Humana/transmissão , Influenza Humana/virologia , Primatas , Sistema Respiratório/metabolismo , Sistema Respiratório/virologia , Medição de Risco , Zoonoses Virais/prevenção & controle , Zoonoses Virais/transmissão , Zoonoses Virais/virologia , Replicação Viral
12.
Molecules ; 28(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37375417

RESUMO

Regulating bulk polymeric carbon nitride (PCN) into nanostructured PCN has long been proven effective in enhancing its photocatalytic activity. However, simplifying the synthesis of nanostructured PCN remains a considerable challenge and has drawn widespread attention. This work reported the one-step green and sustainable synthesis of nanostructured PCN in the direct thermal polymerization of the guanidine thiocyanate precursor via the judicious introduction of hot water vapor's dual function as gas-bubble templates along with a green etching reagent. By optimizing the temperature of the water vapor and polymerization reaction time, the as-prepared nanostructured PCN exhibited a highly boosted visible-light-driven photocatalytic hydrogen evolution activity. The highest H2 evolution rate achieved was 4.81mmol∙g-1∙h-1, which is over four times larger than that of the bulk PCN (1.19 mmol∙g-1∙h-1) prepared only by thermal polymerization of the guanidine thiocyanate precursor without the assistance of bifunctional hot water vapor. The enhanced photocatalytic activity might be attributed to the enlarged BET specific surface area, increased active site quantity, and highly accelerated photo-excited charge-carrier transfer and separation. Moreover, the sustainability of this environmentally friendly hot water vapor dual-function mediated method was also shown to be versatile in preparing other nanostructured PCN photocatalysts derived from other precursors such as dicyandiamide and melamine. This work is expected to provide a novel pathway for exploring the rational design of nanostructured PCN for highly efficient solar energy conversion.

13.
J Clin Invest ; 133(15)2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37338986

RESUMO

Acute graft-versus-host disease (aGVHD) is a severe complication of allogeneic hematopoietic stem cell transplantation. Hematopoietic dysfunction accompanied by severe aGVHD, which may be caused by niche impairment, is a long-standing clinical problem. However, how the bone marrow (BM) niche is damaged in aGVHD hosts is poorly defined. To comprehensively address this question, we used a haplo-MHC-matched transplantation aGVHD murine model and performed single-cell RNA-Seq of nonhematopoietic BM cells. Transcriptional analysis showed that BM mesenchymal stromal cells (BMSCs) were severely affected, with a reduction in cell ratio, abnormal metabolism, compromised differentiation potential, and defective hematopoiesis-supportive function, all of which were validated by functional assays. We found that ruxolitinib, a selective JAK1/2 inhibitor, ameliorated aGVHD-related hematopoietic dysfunction through a direct effect on recipient BMSCs, resulting in improved proliferation ability, adipogenesis/osteogenesis potential, mitochondria metabolism capacity, and crosstalk with donor-derived hematopoietic stem/progenitor cells. By inhibiting the JAK2/STAT1 pathway, ruxolitinib maintained long-term improvement of aGVHD BMSC function. Additionally, ruxolitinib pretreatment in vitro primed BMSCs to better support donor-derived hematopoiesis in vivo. These observations in the murine model were validated in patient samples. Overall, our findings suggest that ruxolitinib can directly restore BMSC function via the JAK2/STAT1 pathway and, in turn, improve the hematopoietic dysfunction caused by aGVHD.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Humanos , Animais , Camundongos , Modelos Animais de Doenças , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/metabolismo , Células-Tronco Mesenquimais/metabolismo , Doença Aguda
14.
Oncol Lett ; 25(6): 255, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37205918

RESUMO

Lung cancer (LC) is the most frequently diagnosed cancer and is the leading cause of cancer-associated death. Serum markers that exhibit high sensitivity and specificity for LC may assist in the diagnosis and prognosis of LC. The banked serum samples from 599 individuals, including 201 healthy controls, 124 patients with benign lung diseases, and 274 LC cases, were used. The serum concentrations of biomarkers were determined by electrochemiluminescence immunoassay and chemiluminescence immunoassay. The results showed that the serum human epididymis secretory protein 4 (HE4) levels in the LC group were significantly higher than in the healthy and benign lung disease groups. The serum levels of HE4, NSE, and CYFRA21-1 were significantly higher in patients with LC compared to those in the benign lung disease group. The area under the area under the curve (AUC) of HE4 for discriminating LC from healthy controls was 0.851 (95% CI, 0.818-0.884) and 0.739 (95% CI, 0.695-0.783), 0.747 (95% CI, 0.704-0.790), 0.626 (95% CI, 0.577-0.676), and 0.700 (95% CI, 0.653-0.747) for NSE, CYFRA21-1, SCC, and ProGRP, respectively. The AUC value of the combination of serum HE4 combined with NSE, CYFRA21-1, SCC, and proGRP for cancer diagnosis was 0.896 (95% CI, 0.868-0.923). In early LC, the AUC value of HE4 for discriminating early LC from healthy controls was 0.802 (95% CI, 0.758-0.845), 0.728 (95% CI, 0.679-0.778), 0.699 (95% CI, 0.646-0.752), 0.605 (95% CI, 0.548-0.662), and 0.685 (95% CI, 0.630-0.739) for NSE, CYFRA21-1, SCC, and ProGRP, respectively. The AUC value of the combination of serum HE4 with NSE, CYFRA21-1, SCC, and proGRP for early LC was 0.867 (95% CI, 0.831-0.903). Serum HE4 is a promising LC biomarker, particularly for early-stage LC. Measuring serum HE4 levels may improve the diagnostic efficiency of LC.

15.
Chemistry ; 29(38): e202300464, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37096756

RESUMO

Helical structure in catalysts has attracted attention and been recently investigated for various catalytic reactions. However, helical transition metal oxides suffer from uncontrollable crystallization processes at high temperatures when being transformed from an amorphous phase into a crystalline structure. Herein, we report a helical anatase TiO2 nanotube for the first time, which has been prepared using a protected crystallization strategy in the confined space of silica. A single chirality of helical TiO2 has been used to track the ordering of the twisted structure. The twisted structure in helical anatase TiO2 nanotube is maintained after a vigorous crystallization process. Helical anatase TiO2 nanotubes possess more accessible active sites and abundant defects of oxygen vacancy and Ti3+ species owing to the twisted structure. The obtained helical anatase TiO2 nanotube exhibits superior photocatalytic activity for hydrogen production without adding any co-catalysts. This work provides new insights into the role of helical structure in transition metal-based catalysts.


Assuntos
Nanotubos , Titânio , Cristalização , Titânio/química , Nanotubos/química , Temperatura Alta
16.
mBio ; 14(3): e0010123, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37097030

RESUMO

Infected hosts possess two alternative strategies to protect themselves against the negative impact of virus infections: resistance, used to abrogate virus replication, and disease tolerance, used to avoid tissue damage without controlling viral burden. The principles governing pathogen resistance are well understood, while less is known about those involved in disease tolerance. Here, we studied bluetongue virus (BTV), the cause of bluetongue disease of ruminants, as a model system to investigate the mechanisms of virus-host interactions correlating with disease tolerance. BTV induces clinical disease mainly in sheep, while cattle are considered reservoirs of infection, rarely exhibiting clinical symptoms despite sustained viremia. Using primary cells from multiple donors, we show that BTV consistently reaches higher titers in ovine cells than cells from cattle. The variable replication kinetics of BTV in sheep and cow cells were mostly abolished by abrogating the cell type I interferon (IFN) response. We identified restriction factors blocking BTV replication, but both the sheep and cow orthologues of these antiviral genes possess anti-BTV properties. Importantly, we demonstrate that BTV induces a faster host cell protein synthesis shutoff in primary sheep cells than cow cells, which results in an earlier downregulation of antiviral proteins. Moreover, by using RNA sequencing (RNA-seq), we also show a more pronounced expression of interferon-stimulated genes (ISGs) in BTV-infected cow cells than sheep cells. Our data provide a new perspective on how the type I IFN response in reservoir species can have overall positive effects on both virus and host evolution. IMPORTANCE The host immune response usually aims to inhibit virus replication in order to avoid cell damage and disease. In some cases, however, the infected host avoids the deleterious effects of infection despite high levels of viral replication. This strategy is known as disease tolerance, and it is used by animal reservoirs of some zoonotic viruses. Here, using a virus of ruminants (bluetongue virus [BTV]) as an experimental system, we dissected virus-host interactions in cells collected from species that are susceptible (sheep) or tolerant (cow) to disease. We show that (i) virus modulation of the host antiviral type I interferon (IFN) responses, (ii) viral replication kinetics, and (iii) virus-induced cell damage differ in tolerant and susceptible BTV-infected cells. Understanding the complex virus-host interactions in disease tolerance can allow us to disentangle the critical balance between protective and damaging host immune responses.


Assuntos
Bluetongue , Interferon Tipo I , Feminino , Ovinos , Animais , Bovinos , Interferon Tipo I/genética , Bluetongue/metabolismo , Viremia , Antivirais
17.
Phytochemistry ; 210: 113673, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37030588

RESUMO

Six undescribed tanshinones, (+)-2-Cl-tanshindiol C (1), (-)-2-Cl-tanshindiol C (2), (+)-tanshinoic acid D (3), (-)-tanshinoic acid D (4), (-)-tanshinoic acid E (5), and (+)-tanshinoic acid E (6), were isolated from the rhizome of Salvia miltiorrhiza Bunge. Their structures were elucidated based on the spectroscopic data (UV, IR, HR-ESI-MS, and NMR). The bioactive assays of all these compounds for the antioxidant activities in cardiomyocytes upon hypoxia stimulation were evaluated. The results suggested that compounds 5 and 6 exhibited good antioxidant activities in cardiomyocytes and the cell survival rates were 46.3% and 57.9% (10-5 mol/L), respectively.


Assuntos
Salvia miltiorrhiza , Salvia miltiorrhiza/química , Antioxidantes/farmacologia , Abietanos/farmacologia , Abietanos/química , Rizoma/química , Raízes de Plantas/química
18.
Front Nutr ; 10: 1143511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937352

RESUMO

Fruits and vegetables contain numerous nutrients, such as vitamins, minerals, phenolic compounds, and dietary fibers. They reduce the incidence of cardiovascular diseases and the risk of certain chronic diseases, and improve the antioxidant and anti-inflammatory capacity. Moreover, melatonin was found in various fruits and vegetables species. Melatonin acts as a multifunctional compound to participate in various physiological processes. In recent years, many advances have been found that melatonin is also appraised as a key modulator on the fruits and vegetables post-harvest preservation. Fruits and vegetables post-harvest usually elicit reactive oxygen species (ROS) generation and accumulation. Excess ROS stimulate cell damage, protein structure destruction, and tissue aging, and thereby reducing their quality. Numerous studies find that exogenous application of melatonin modulates ROS homeostasis by regulating the antioxidant enzymes and non-enzymatic antioxidants systems. Further evidences reveal that melatonin often interacts with hormones and other signaling molecules, such as ROS, nitric oxide (NO), hydrogen sulfide (H2S), and etc. Among these 'new' molecules, crosstalks of melatonin and ROS, especially the H2O2 produced by RBOHs, are provided in fruits and vegetables post-harvest preservation in this review. It will provide reference for complicated integration of both melatonin and ROS as signal molecules in future study.

19.
Chemistry ; 29(2): e202202678, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36210336

RESUMO

Promoting charge separation, constructing active sites, and improving the utilization of metal atoms are very important for the design of efficient photocatalysts. A simultaneous loading of Ni2 P cocatalysts on the inner and outer surfaces of mesoporous P-doped carbon nitride hollow nanospheres (PCNHS) to construct a Ni2 P@PCNHS@Ni2 P photocatalyst is reported. Ni2 P cocatalysts loading provides enough active sites on both the inner and outer surfaces for proton reduction, and the formed heterojunctions simultaneously promote the migration and separation of the photogenerated charges on the inner and outer surfaces. The photocatalytic reaction proceeds simultaneously on the inner and outer surfaces of Ni2 P@PCNHS@Ni2 P, which leads to a significantly improved photocatalytic water splitting performance and enhanced atomic utilization. Notably, the hydrogen evolution rate of Ni2 P@PCNHS@Ni2 P is 2.4 times higher than that of Pt-loaded PCNHS. The findings guide the design of hollow nanostructured composites with high-boosting photocatalytic performance.

20.
Gigascience ; 112022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36399061

RESUMO

BACKGROUND: A virus-infected cell triggers a signalling cascade, resulting in the secretion of interferons (IFNs), which in turn induces the upregulation of the IFN-stimulated genes (ISGs) that play a role in antipathogen host defence. Here, we conducted analyses on large-scale data relating to evolutionary gene expression, sequence composition, and network properties to elucidate factors associated with the stimulation of human genes in response to IFN-α. RESULTS: We find that ISGs are less evolutionary conserved than genes that are not significantly stimulated in IFN experiments (non-ISGs). ISGs show obvious depletion of GC content in the coding region. This influences the representation of some compositions following the translation process. IFN-repressed human genes (IRGs), downregulated genes in IFN experiments, can have similar properties to the ISGs. Additionally, we design a machine learning framework integrating the support vector machine and novel feature selection algorithm that achieves an area under the receiver operating characteristic curve (AUC) of 0.7455 for ISG prediction. Its application in other IFN systems suggests the similarity between the ISGs triggered by type I and III IFNs. CONCLUSIONS: ISGs have some unique properties that make them different from the non-ISGs. The representation of some properties has a strong correlation with gene expression following IFN-α stimulation, which can be used as a predictive feature in machine learning. Our model predicts several genes as putative ISGs that so far have shown no significant differential expression when stimulated with IFN-α in the cell/tissue types in the available databases. A web server implementing our method is accessible at http://isgpre.cvr.gla.ac.uk/. The docker image at https://hub.docker.com/r/hchai01/isgpre can be downloaded to reproduce the prediction.


Assuntos
Interferon-alfa , Aprendizado de Máquina , Humanos , Interferon-alfa/farmacologia , Transdução de Sinais
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