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1.
Front Nutr ; 11: 1390256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721034

RESUMO

Edible mushrooms are an important source of nutraceuticals and for the discovery of bioactive metabolites as pharmaceuticals. In this work, six new polyphenolic metabolites suillusol A-D (1-4), suillusinoic acid (5), ethyl suillusinoate (6), were isolated from the Suillus granulatus. The structures of new compounds were elucidated using high-resolution electrospray ionization mass spectroscopy, nuclear magnetic resonance data, and single-crystal X-ray diffraction analysis. As far as we know, compound 1 represents an unprecedented type of natural product and compound 3 represents a new type of polyphenol fungal pigment, which may be biosynthetically related to thelephoric acid. The cytotoxicity against HepG2 cells of the new compounds were also evaluated. Compound 2 demonstrate significant inhibitory activity against HepG2 cells with IC50 values of 10.85 µM, surpassing that of positive control cisplatin. Moreover, compound 1 and 3 also exhibited moderate cytotoxic activity with their IC50 values measured at 35.60 and 32.62 µM, respectively. Our results indicate that S. granulatus is a rich source of chemical constituents that may provide new lead compounds for the development of anticancer agents.

2.
Bioresour Technol ; 402: 130828, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38734260

RESUMO

This study investigated the influence of yeast extract addition, carbon source, and photoperiod on the growth dynamics of Auxenochlorella pyrenoidosa FACHB-5. Employing response surface methodology, the culture strategy was optimized, resulting in the following optimal conditions: yeast extract addition at 0.75 g L-1, glucose concentration of 0.83 g L-1, and a photoperiod set at Light: Dark = 18 h: 6 h. Under these conditions, the biomass reached 1.76 g L-1 with a protein content of 750.00 g L-1, containing 40 % of essential amino acids, representing a 1.52-fold increase. Proteomic analysis revealed that the targeted cultivation strategy up-regulated genes involved in microalgal protein synthesis. The combined effect of yeast extract and glucose enhanced both the glutamine synthetase-glutamate synthetase mechanism and the free amino acid content.

3.
Int J Gen Med ; 17: 2113-2128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766598

RESUMO

Purpose: Evidence has indicated that PDZD11 is involved in regulating adherens junction. However, the distinct effect of its aberrant expression on epithelial ovarian cancer (EOC) awaits clarification. Methods: In this study, public databases (Gene Expression Omnibus, The Cancer Genome Atlas, and The Genotype-Tissue Expression), online analysis tools (Kaplan-Meier plotter and TIMER), and data analysis methods (Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and the CIBERSORT algorithm) were fully utilized to analyze the differential expression, diagnostic efficiency, prognostic significance, potential function, and correlation with immune infiltration of PDZD11. The differential expression of PDZD11 was tested by immunohistochemistry in EOC tissues (78 cases) and control tissues (37 cases). Results: Our results indicate that PDZD11 was remarkably overexpressed in EOC, which was associated with advanced cancer stages, no lymphatic metastasis status, and poor prognosis. Moreover, PDZD11 played a role in cell adhesion, cell proliferation, and immune responses. Also, PDZD11 was significantly related to the abundances of infiltrating immune cells in EOC, including neutrophils, macrophages, dendritic cells, CD8+ T cells, and CD4+ T cells, and its expression was positively co-expressed with well-known immune checkpoints, including TIGIT, TIM3, LAG3, CTLA4, and PD-1. Conclusion: These results suggest that PDZD11 could be a potential diagnostic and prognostic biomarker associated with immune infiltration in EOC, and our findings might help elucidate the function of PDZD11 in carcinogenesis.

4.
Cell Biol Int ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38706122

RESUMO

Cisplatin is commonly used for the chemotherapy of tongue squamous cell carcinoma (TSCC); however, adverse side effects and drug resistance impact its therapeutic efficacy. Capsaicin is an active ingredient in chili peppers that exerts antitumor effects, whether it exerts antitumor effects on cisplatin-resistant cells remains unknown. Therefore, in this study, we investigated the effect of capsaicin on cisplatin resistance in TSCC cells and explored the underlying mechanisms. A cisplatin-resistant TSCC cell line was established by treated with increasing cisplatin concentrations. Combined treatment with cisplatin and capsaicin decreased the glucose consumption and lactate dehydrogenase activity and increased the adenosine triphosphate production both in vitro and in vivo, suggesting the inhibition of the Warburg effect. Moreover, this combined treatment induced cell apoptosis and significantly upregulated the levels of proapoptotic proteins, such as Bax, cleaved caspase-3, -7, and -9, and apoptosis-inducing factor. In contrast, levels of the antiapoptotic protein, Bcl-2, were downregulated. Additionally, LKB1 and AMPK activities were stimulated, whereas those of AKT and mTOR were suppressed. Notably, AMPK knockdown abolished the inhibitory effects of capsaicin and cisplatin on the AKT/mTOR signaling pathway and Warburg effect. Overall, combined treatment with capsaicin and cisplatin reversed cisplatin resistance by inhibiting the Warburg effect and facilitating mitochondrial-dependent apoptosis via the AMPK/AKT/mTOR axis. Our findings suggest combination therapy with capsaicin and cisplatin as a potentially novel strategy and highlight capsaicin as a promising adjuvant drug for TSCC treatment.

5.
Technol Cancer Res Treat ; 23: 15330338241249692, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706262

RESUMO

PURPOSE: PIWI-interacting RNAs (piRNAs) are a type of noncoding small RNA that can interact with PIWI-like RNA-mediated gene silencing (PIWIL) proteins to affect biological processes such as transposon silencing through epigenetic effects. Recent studies have found that piRNAs are widely dysregulated in tumors and associated with tumor progression and a poor prognosis. Therefore, this study aimed to investigate the effect of piR-1919609 on the proliferation, apoptosis, and drug resistance of ovarian cancer cells. METHODS: In this study, we used small RNA sequencing to screen and identify differentially expressed piRNAs in primary ovarian cancer, recurrent ovarian cancer, and normal ovaries. A large-scale verification study was performed to verify the expression of piR-1919609 in different types of ovarian tissue, including ovarian cancer tissue and normal ovaries, by RT-PCR and to analyze its association with the clinical prognosis of ovarian cancer. The expression of PIWILs in ovarian cancer was verified by RT-PCR, Western blotting and immunofluorescence. The effects of piR-1919609 on ovarian cancer cell proliferation, apoptosis and drug resistance were studied through in vitro and in vivo models. RESULTS: (1) piR-1919609 was highly expressed in platinum-resistant ovarian cancer tissues (p < 0.05), and this upregulation was significantly associated with a poor prognosis and a shorter recurrence time in ovarian cancer patients (p < 0.05). (2) PIWIL2 was strongly expressed in ovarian cancer tissues (p < 0.05). It was expressed both in the cytoplasm and nucleus of ovarian cancer cells. (3) Overexpression of piR-1919609 promoted ovarian cancer cell proliferation, inhibited apoptosis, and promoted tumor growth in nude mice. (4) Inhibition of piR-1919609 effectively reversed ovarian cancer drug resistance. CONCLUSION: In summary, we showed that piR-1919609 is involved in the regulation of drug resistance in ovarian cancer cells and might be an ideal potential target for reversing platinum resistance in ovarian cancer.


Assuntos
Apoptose , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas , RNA Interferente Pequeno , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , RNA Interferente Pequeno/genética , Prognóstico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Platina/uso terapêutico , Platina/farmacologia
6.
J Gynecol Oncol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38710531

RESUMO

OBJECTIVE: To investigate the association of primary tumor site with prognosis in vulvar cancer, stratified by vulvar squamous cell carcinoma (SCC) and non-SCC histological types. METHODS: This population-based retrospective study enrolled patients with vulvar cancer from the Surveillance, Epidemiology, and End Results database between January 2000 and December 2018. The primary outcome was cancer-specific survival (CSS). The prognostic difference between labium majus, labium minus and clitoris groups was investigated using Kaplan-Meier analyses and Cox proportional hazards regression analyses. RESULTS: A total of 3,465 eligible patients with vulvar cancer were included with a mean age of 54.5 years. Among the 1,076 (31.1%) patients with non-SCC, the multivariate Cox regression analyses showed that labium minus-sited disease (hazard ratio [HR]=1.85; 95% confidence interval [CI]=1.27-2.71; p=0.001) and clitoris-sited disease (HR=2.37; 95% CI=1.47-3.85; p<0.001) were significantly associated with worse CSS, compared with labium majus-sited disease. However, among the 2,389 (68.9%) patients with SCC, no significant association of primary tumor site with CSS was found (p>0.05). Kaplan-Meier analyses also showed that the primary tumor site had a significant prognostic effect in vulvar non-SCC (p<0.001) but not in vulvar SCC (p=0.330). CONCLUSION: Among vulvar non-SCC, patients with labium minus-sited disease had a significantly worse prognosis than those with labium majus-sited disease, and a significantly better prognosis than those with clitoris-sited disease. Gynecologic oncologists should consider the prognostic effect of primary tumor site in vulvar non-SCC, and make optimal, personalized treatment and surveillance strategies based on different primary tumor sites.

7.
Front Microbiol ; 15: 1408013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756729

RESUMO

In order to control the occurrence of ginseng root rot caused by Fusarium solani (Mart.) Sacc., the antifungal compounds of the mushroom Suillus bovinus were investigated. And three new alkaloids (1-3), named bovinalkaloid A-C, along with one known analog (4), were isolated and identified by bioassay-guided isolation and spectroscopic analyses. Compound 1 strongly inhibited the mycelial growth and spore germination of F. solani with minimum inhibitory concentration of 2.08 mM. Increases in electrical conductivity, nucleic acid, and protein contents, and decreases in lipid content showed that the membrane permeability and integrity were damaged by compound 1. Compound 1 also increased the contents of malondialdehyde and hydrogen peroxide and the activities of antioxidant enzymes, indicating that lipid peroxidation had taken place in F. solani. Compound 1 may serve as a natural alternative to synthetic fungicides for the control of ginseng root rot.

8.
PLoS One ; 19(5): e0301610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743774

RESUMO

In the process of horizontal well construction, the working environment in the well is very complicated. It is difficult to determine the actual deformation and force of the coiled tubing in the wellbore from the load change at the wellhead along. In addition, the coiled tubing wrapped around the reel and entering the wellbore through the injection head may cause an initial residual bending. In this paper, the mathematical model of the coiled tubing under axial load during buckling deformation is established, and the analytical solution with the time term is derived by reasonable simplification of the model. The effect of residual bending on the post-sinusoidal buckling of the coiled tubing in the horizontal well was investigated using the separation variable method. The effect of residual bending variations on the well wall contact forces is analyzed. The research shows that the initial parameter Г is the main factor influencing the post-sinusoidal buckling of the coiled tubing with residual bending. The larger the parameter value Г, the greater the effect of the residual bending on the post-sinusoidal buckling deformation of the coiled tubing, and the earlier the critical point of the mixed sinusoidal-helical buckling of the coiled tubing appears. The compression velocity of the coiled tubing has a significant effect on the well wall contact force. The faster the compression, the greater the contact force. By introducing the time term and the separation variable, this paper provides a new method and theoretical basis for further study of the process of entering sinusoidal-helical buckling of the coiled tubing with initial residual bending.


Assuntos
Modelos Teóricos , Estresse Mecânico
9.
Opt Lett ; 49(7): 1660-1663, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560830

RESUMO

We report a high-performance wavelength-switchable near-infrared Pr3+:LiYF4 (Pr:YLF) laser by InGaN laser diode (LD) pumping. The 895, 922, and 924 nm lasers with low emission cross sections in the Pr:YLF crystal have been successfully realized using a birefringent filter Lyot as well as designing and optimizing optical thin films and the laser resonant cavity. The maximum output powers of the 895, 922, and 924 nm lasers are 2.01, 1.92, and 1.95 W, respectively. As far as we know, these are the highest power for Pr:YLF lasers at 895, 922, and 924 nm so far. The beam quality M x2 and M y2 factors are measured to be 1.85 and 1.71 at 895 nm, 1.94 and 1.67 at 922 nm, and 1.76 and 1.60 at 924 nm, respectively. The laser output power fluctuates within ±3%. In addition, the transmittance of the Lyot is theoretically calculated to achieve laser wavelength switching. The successful realization of the wavelength-switchable watt-level continuous wave near-infrared Pr:YLF laser can provide many practical applications in biomedicine and other fields.

10.
Postgrad Med ; : 1-14, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38635593

RESUMO

Gallbladder cancer is a common type of biliary tract tumor. Optimal management for early stage cases typically involves radical excision as the primary treatment modality. Various surgical techniques, including laparoscopic, robotic, and navigational surgery, have demonstrated favorable clinical outcomes in radical gallbladder excision. Unfortunately, most patients are ineligible for surgical intervention because of the advanced stage of the disease upon diagnosis. Consequently, non-surgical interventions, such as chemotherapy, radiotherapy, immunotherapy, and targeted therapy, have become the mainstay of treatment for patients in advanced stages. This review focuses on elucidating various surgical techniques as well as advancements in immunotherapy and targeted therapy in the context of recent advancements in gallbladder cancer research.

11.
J Virol ; 98(5): e0025324, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591878

RESUMO

Coronavirus (CoV) 3C-like protease (3CLpro) is essential for viral replication and is involved in immune escape by proteolyzing host proteins. Deep profiling the 3CLpro substrates in the host proteome extends our understanding of viral pathogenesis and facilitates antiviral drug discovery. Here, 3CLpro from porcine epidemic diarrhea virus (PEDV), an enteropathogenic CoV, was used as a model which to identify the potential 3CLpro cleavage motifs in all porcine proteins. We characterized the selectivity of PEDV 3CLpro at sites P5-P4'. We then compiled the 3CLpro substrate preferences into a position-specific scoring matrix and developed a 3CLpro profiling strategy to delineate the protein substrate landscape of CoV 3CLpro. We identified 1,398 potential targets in the porcine proteome containing at least one putative cleavage site and experimentally validated the reliability of the substrate degradome. The PEDV 3CLpro-targeted pathways are involved in mRNA processing, translation, and key effectors of autophagy and the immune system. We also demonstrated that PEDV 3CLpro suppresses the type 1 interferon (IFN-I) cascade via the proteolysis of multiple signaling adaptors in the retinoic acid-inducible gene I (RIG-I) signaling pathway. Our composite method is reproducible and accurate, with an unprecedented depth of coverage for substrate motifs. The 3CLpro substrate degradome establishes a comprehensive substrate atlas that will accelerate the investigation of CoV pathogenicity and the development of anti-CoV drugs.IMPORTANCECoronaviruses (CoVs) are major pathogens that infect humans and animals. The 3C-like protease (3CLpro) encoded by CoV not only cleaves the CoV polyproteins but also degrades host proteins and is considered an attractive target for the development of anti-CoV drugs. However, the comprehensive characterization of an atlas of CoV 3CLpro substrates is a long-standing challenge. Using porcine epidemic diarrhea virus (PEDV) 3CLpro as a model, we developed a method that accurately predicts the substrates of 3CLpro and comprehensively maps the substrate degradome of PEDV 3CLpro. Interestingly, we found that 3CLpro may simultaneously degrade multiple molecules responsible for a specific function. For instance, it cleaves at least four adaptors in the RIG-I signaling pathway to suppress type 1 interferon production. These findings highlight the complexity of the 3CLpro substrate degradome and provide new insights to facilitate the development of anti-CoV drugs.


Assuntos
Vírus da Diarreia Epidêmica Suína , Animais , Suínos , Especificidade por Substrato , Proteases 3C de Coronavírus/metabolismo , Proteoma/metabolismo , Humanos , Proteólise , Interferon Tipo I/metabolismo , Infecções por Coronavirus/virologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/veterinária , Células HEK293 , Proteínas Virais/metabolismo , Proteínas Virais/genética , Replicação Viral
12.
Nucleic Acids Res ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661236

RESUMO

RNA-targeting type VI CRISPR-Cas effectors are widely used in RNA applications. Cas13h is a recently identified subtype of Cas13 ribonuclease, with strong RNA cleavage activity and robust in vivo RNA knockdown efficiency. However, little is known regarding its biochemical properties and working mechanisms. Biochemical characterization of Cas13h1 indicated that it lacks in vitro pre-crRNA processing activity and adopts a central seed. The cleavage activity of Cas13h1 is enhanced by a R(G/A) 5'-PFS, and inhibited by tag:anti-tag RNA pairing. We determined the structures of Cas13h1-crRNA binary complex at 3.1 Å and Cas13h1-crRNA-target RNA ternary complex at 3.0 Å. The ternary complex adopts an elongated architecture, and encodes a nucleotide-binding pocket within Helical-2 domain to recognize the guanosine at the 5'-end of the target RNA. Base pairing between crRNA guide and target RNA disrupts Cas13h1-guide interactions, leading to dramatic movement of HEPN domains. Upon target RNA engagement, Cas13h1 adopts a complicated activation mechanism, including separation of HEPN catalytic residues and destabilization of the active site loop and NTD domain, to get activated. Collectively, these insights expand our understanding into Cas13 effectors.

13.
BMC Surg ; 24(1): 117, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643065

RESUMO

BACKGROUND: This study investigated the clinical application of the indocyanine green (ICG) fluorescence navigation technique in bile duct identification during laparoscopic common bile duct exploration (LCBDE) for complex hepatolithiasis. METHODS: Eighty patients with complex hepatolithiasis were admitted to our department between January 2022 and June 2023 and randomly divided into control and observation groups. The control group underwent conventional LCBDE, while the observation group underwent LCBDE guided by ICG fluorescence. RESULTS: Intraoperatively, the observation group had shorter operation and search times for the common bile duct (CBD), as well as reduced intraoperative blood loss and fewer complications, such as conversion to laparotomy and various injuries (gastroduodenal, colon, pancreatic, and vascular) than the control group, with statistical significance (P < 0.05). Postoperatively, the observation group had lower rates of postoperative bile leakage, abdominal infection, postoperative hemorrhage, and residual stone than the control group. Additionally, the observation group demonstrated significantly shorter times for resuming flatus, removal of the abdominal drainage tube, and hospitalization than the control group, with statistical significance (P < 0.05). CONCLUSION: ICG fluorescence navigation technology effectively visualizes the bile duct, improves its identification rate, shortens the operation time, prevents biliary tract injury, and reduces the occurrence of complications.


Assuntos
Coledocolitíase , Laparoscopia , Litíase , Hepatopatias , Humanos , Coledocolitíase/cirurgia , Ducto Colédoco/cirurgia , Verde de Indocianina , Laparoscopia/métodos , Tempo de Internação , Litíase/cirurgia , Hepatopatias/cirurgia , Estudos Retrospectivos
14.
Phytomedicine ; 129: 155661, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38677269

RESUMO

BACKGROUND: Gallbladder cancer (GBC) poses a significant risk to human health. Its development is influenced by numerous factors, particularly the homeostasis of reactive oxygen species (ROS) within cells. This homeostasis is crucial for tumor cell survival, and abnormal regulation of ROS is associated with the occurrence and progression of many cancers. Dihydrotanshinone I (DHT I), a biologically effective ingredient isolated from Salvia miltiorrhiza, has exhibited cytotoxic properties against various tumor cells by inducing apoptosis. However, the precise molecular mechanisms by which dht I exerts its cytotoxic effects remain unclear. PURPOSE: To explore the anti-tumor impact of dht I on GBC and elucidate the potential molecular mechanisms. METHODS: The proliferation of GBC cells, NOZ and SGC-996, was assessed using various assays, including CCK-8 assay, colony formation assay and EdU staining. We also examined cell apoptosis, cell cycle progression, ROS levels, and alterations in mitochondrial membrane potential to delve into the intricate molecular mechanism. Quantitative PCR (qPCR), immunofluorescence staining, and Western blotting were performed to evaluate target gene expression at both the mRNA and protein levels. The correlation between nuclear factor erythroid 2-related factor 2 (Nrf2) and kelch-like ECH-associated protein 1 (Keap1) were examined using co-immunoprecipitation. Finally, the in vivo effect of dht I was investigated using a xenograft model of gallbladder cancer in mice. RESULTS: Our research findings indicated that dht I exerted cytotoxic effects on GBC cells, including inhibiting proliferation, disrupting mitochondrial membrane potential, inducing oxidative stress and apoptosis. Our in vivo studies substantiated the inhibition of dht I on tumor growth in xenograft nude mice. Mechanistically, dht I primarily targeted Nrf2 by promoting Keap1 mediated Nrf2 degradation and inhibiting protein kinase C (PKC) induced Nrf2 phosphorylation. This leads to the suppression of Nrf2 nuclear translocation and reduction of its target gene expression. Moreover, Nrf2 overexpression effectively counteracted the anti-tumor effects of dht I, while Nrf2 knockdown significantly enhanced the inhibitory effect of dht I on GBC. Meanwhile, PKC inhibitors and nuclear import inhibitors increased the sensitivity of GBC cells to dht I treatment. Conversely, Nrf2 activators, proteasome inhibitors, antioxidants and PKC activators all antagonized dht I induced apoptosis and ROS generation in NOZ and SGC-996 cells. CONCLUSION: Our findings indicated that dht I inhibited the growth of GBC cells by regulating the Keap1-Nrf2 signaling pathway and Nrf2 phosphorylation. These insights provide a strong rationale for further investigation of dht I as a potential therapeutic agent for GBC treatment.

15.
Emerg Microbes Infect ; 13(1): 2332653, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38517703

RESUMO

Coinfection with multiple viruses is a common phenomenon in clinical settings and is a crucial driver of viral evolution. Although numerous studies have demonstrated viral recombination arising from coinfections of different strains of a specific species, the role of coinfections of different species or genera during viral evolution is rarely investigated. Here, we analyzed coinfections of and recombination events between four different swine enteric coronaviruses that infect the jejunum and ileum in pigs, including porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and swine acute diarrhea syndrome coronavirus (SADS-CoV), and a deltacoronavirus, porcine deltacoronavirus (PDCoV). Various coinfection patterns were observed in 4,468 fecal and intestinal tissue samples collected from pigs in a 4-year survey. PEDV/PDCoV was the most frequent coinfection. However, recombination analyses have only detected events involving PEDV/TGEV and SADS-CoV/TGEV, indicating that inter-species recombination among coronaviruses is most likely to occur within the same genus. We also analyzed recombination events within the newly identified genus Deltacoronavirus and found that sparrows have played a unique host role in the recombination history of the deltacoronaviruses. The emerging virus PDCoV, which can infect humans, has a different recombination history. In summary, our study demonstrates that swine enteric coronaviruses are a valuable model for investigating the relationship between viral coinfection and recombination, which provide new insights into both inter- and intraspecies recombination events among swine enteric coronaviruses, and extend our understanding of the relationship between coronavirus coinfection and recombination.


Assuntos
Alphacoronavirus , Coinfecção , Infecções por Coronavirus , Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Vírus da Gastroenterite Transmissível , Humanos , Suínos , Animais , Coinfecção/veterinária , Infecções por Coronavirus/veterinária , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Gastroenterite Transmissível/genética , Recombinação Genética
16.
Nat Commun ; 15(1): 2692, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538592

RESUMO

The Silent Information Regulator 2 (SIR2) protein is widely implicated in antiviral response by depleting the cellular metabolite NAD+. The defense-associated sirtuin 2 (DSR2) effector, a SIR2 domain-containing protein, protects bacteria from phage infection by depleting NAD+, while an anti-DSR2 protein (DSR anti-defense 1, DSAD1) is employed by some phages to evade this host defense. The NADase activity of DSR2 is unleashed by recognizing the phage tail tube protein (TTP). However, the activation and inhibition mechanisms of DSR2 are unclear. Here, we determine the cryo-EM structures of DSR2 in multiple states. DSR2 is arranged as a dimer of dimers, which is facilitated by the tetramerization of SIR2 domains. Moreover, the DSR2 assembly is essential for activating the NADase function. The activator TTP binding would trigger the opening of the catalytic pocket and the decoupling of the N-terminal SIR2 domain from the C-terminal domain (CTD) of DSR2. Importantly, we further show that the activation mechanism is conserved among other SIR2-dependent anti-phage systems. Interestingly, the inhibitor DSAD1 mimics TTP to trap DSR2, thus occupying the TTP-binding pocket and inhibiting the NADase function. Together, our results provide molecular insights into the regulatory mechanism of SIR2-dependent NAD+ depletion in antiviral immunity.


Assuntos
Sirtuínas , Sirtuínas/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , NAD/metabolismo , NAD+ Nucleosidase/metabolismo , Sirtuína 2/metabolismo , Ligação Proteica , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo
17.
Plant Dis ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506905

RESUMO

The occurrence of rust fungi on Corydalis bungeana Turcz. and Salix babylonica L. were found in same area of Hebei Province, China from 2022 to 2023. The life cycle connection of these rust fungi was suspected because Peng et al. (2022) reported the life cycle of Melampsora ferrinii Toome & Aime by inoculations, producing spermogonia and aecia on Corydalis species, and uredinia on S. babylonica. The morphology of the uredinial and telial stages on S. babylonica collected in the field was identical with the description of M. ferrinii by Toome and Aime (2015), and its identity was confirmed by phylogenetic analyses using the method of Ji et al. (2020) (LSU-PP087777, ITS-PP091274; Similarity with M. ferrinii: LSU-100%, ITS-99.85%). To confirm the life cycle of this rust fungus, inoculations were conducted on C. bungeana with basidiospores obtained from the teliospores on fallen leaves of Salix babylonica. The fallen leaves producing basidiospores were cut into small pieces (ca. 5 mm2) and placed on healthy leaves of C. bungeana. The inoculated plants were kept in a moist plastic box in darkness at 15-20℃ for 2 days and then transferred to the floor near windows at about 15-20℃ for observations. Ten days after inoculations small yellow spots of spermogonia appeared on the upper surface of the leaves of C. bungeana. About 7 days later, pale yellow aecia with aeciospores were produced mainly on the under surface of the leaves and petioles. The morphology of rust fungus on C. bungeana collected from the fields and obtained by inoculations was identical with the description by Peng et al. (2022). Phylogenetic analyses also showed that a specimen on C. bungeana collected from the field (LSU-OR607838, ITS-OR612063) were included into the same clade of M. ferrinii (Similarity: LSU-100 %, ITS-99.85). Based on morphology, inoculations and DNA sequence analyses, the rust fungi on C. bungeana and S. babylonica are identified as different stages of life cycle of M. ferrinii. This rust fungus has been reported to produce spermogonia and aecia on C. acuminata Franch., C. edulis Maxim. and C. racemosa (Thunb.) Pers. in China (Peng et al. 2022), and uredinia and telia on S. babylonica in USA, Argentina and Iran (Toome and Aime 2015, Abbasi et al. 2024), and on Salix sp. in Chile (Zapata 2016). Therefore, C. bungeana is a new host for M. ferrinii, and its field occurrence on S. babylonica is reported for the first time in China although Peng et al. (2022) reported successful results in its inoculations to S. babylonica in China. This report contributes to the control of rust diseases caused by this species. Specimens used in this experiment were deposited in the Fungal Herbarium of the Jilin Agricultural University, Changchun, China (HMJAU) and sequences newly analyzed were deposited in GenBank.

18.
Nano Lett ; 24(11): 3378-3385, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456747

RESUMO

This paper reports how a hybrid system composed of transparent dielectric lattices over a metal mirror can produce high-quality lattice resonances for unidirectional lasing. The enhanced electromagnetic fields are concentrated in the cladding of the periodic dielectric structures and away from the metal. Based on a mirror-image model, we reveal that such high-quality lattice resonances are governed by bound states in the continuum resulting from destructive interference. Using hexagonal arrays of titanium dioxide nanoparticles on a silica-coated silver mirror, we observed lattice resonances with quality factors of up to 2750 in the visible regime. With the lattice resonances as optical feedback and dye solution as the gain medium, we demonstrated unidirectional lasing under optical pumping, where the array size was down to 100 µm × 100 µm. Our scheme can be extended to other spectral regimes to simultaneously achieve strongly enhanced surface fields and high quality factors.

19.
J Gastrointest Oncol ; 15(1): 190-202, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38482211

RESUMO

Background: The long non-coding RNA (lncRNA) prostate cancer-associated transcript 6 (PCAT6) has been studied in many cancers, yet its relationship with colorectal cancer (CRC) remains poorly defined. Here, we conducted an analysis of The Cancer Genome Atlas (TCGA) database to better clarify the role of PCAT6 in this cancer type. Methods: Wilcoxon rank-sum tests were utilized to assess relative levels of PCAT6 in CRC tumors and normal tissues, while logistic regression analyses were utilized to compare the relationships between PCAT6 levels and clinicopathological findings. Kaplan-Meier curves and Cox regression analyses were used to gauge correlations between PCAT6 and patient survival outcomes, while the biological roles of this lncRNA were investigated via a gene set enrichment analysis (GSEA) approach. The expression level of PCAT6 in CRC cell lines was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Results: PCAT6 levels were significantly correlated with CRC patient lymph node metastasis (N) stage [odds ratio (OR) =1.8 for N1 & N2 vs. N0], lymphatic invasion [OR =1.9 for yes vs. no), distant metastasis (M stage) (OR =2.1 for M1 vs. M0), carcinoembryonic antigen (CEA) level (OR =1.9 for >5 vs. ≤5), perineural invasion (OR =1.9 for yes vs. no), pathologic stage (OR =1.9 for stage III/IV vs. stage I/II), and neoplasm type (OR =2.1 for rectal adenocarcinoma vs. colon adenocarcinoma) (all P<0.05). CRC patients expressing higher PCAT6 levels exhibited poorer survival outcomes than those expressing low levels of this lncRNA (P=0.017), and in univariate analyses, higher PCAT6 levels were linked to worse overall survival [hazard ratio (HR) =1.540; 95% confidence interval (CI): 1.079-2.199; P=0.017], with this relationship also being preserved in a multivariate analysis (HR =6.892; 95% CI: 1.713-27.727, P=0.007). GSEA revealed high PCAT6 expression to be linked to differential DNA methylation enrichment, with high PCAT6 levels being associated with changes in base excision repair, cellular senescence, G2/M DNA damage checkpoint, chromatin-modifying enzyme, and gene silencing by RNA activity. The high expression of lncRNA PCAT6 in CRC cell lines was demonstrated by PCR experiments. Conclusions: PCAT6 represents a promising prognostic biomarker of poor CRC patient survival outcomes, with DNA methylation and RNA-mediated gene silencing being potentially promising mechanistic pathways whereby this lncRNA may shape patient outcomes.

20.
J Med Chem ; 67(6): 4726-4738, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38489247

RESUMO

Cryptococcus neoformans (C. neoformans) and Candida albicans (C. albicans) are classified as the critical priority groups among the pathogenic fungi, highlighting the urgent need for developing more effective antifungal therapies. On the basis of antifungal natural product sampangine, herein, a series of tricyclic oxime and oxime ether derivatives were designed. Among them, compound WZ-2 showed excellent inhibitory activity against C. neoformans (MIC80 = 0.016 µg/mL) and synergized with fluconazole to treat resistant C. albicans (FICI = 0.078). Interestingly, compound WZ-2 effectively inhibited virulence factors (e.g., capsule, biofilm, and yeast-to-hypha morphological transition), suggesting the potential to overcome drug resistance. In a mouse model of cryptococcal meningitis, compound WZ-2 (5 mg/kg) effectively reduced the brain C. neoformans H99 burden. Furthermore, compound WZ-2 alone and its combination with fluconazole also significantly reduced the kidney burden of the drug-resistant strain (0304103) and sensitive strain (SC5314) of C. albicans.


Assuntos
Alcaloides , Candidíase , Criptococose , Cryptococcus neoformans , Compostos Heterocíclicos de 4 ou mais Anéis , Naftiridinas , Animais , Camundongos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Candidíase/tratamento farmacológico , Candida albicans , Testes de Sensibilidade Microbiana
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