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1.
Stem Cell Res Ther ; 15(1): 195, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956738

RESUMO

BACKGROUND: Nowadays, companion and working dogs hold significant social and economic importance. Dry eye, also known as dry keratoconjunctivitis (KCS), a common disease in ophthalmology, can readily impact a dog's working capacity and lead to economic losses. Although there are several medications available for this disease, all of them only improve the symptoms on the surface of the eye, and they are irritating and not easy to use for long periods of time. Adipose-derived mesenchymal stem cells (ADMSC) are promising candidates for tissue regeneration and disease treatment. However, long-term in vitro passaging leads to stemness loss of ADMSC. Here, we aimed to use ADMSC overexpressing Secreted Protein Acidic and Rich in Cysteine (SPARC) to treat 0.25% benzalkonium chloride-treated dogs with dry eye to verify its efficacy. For in vitro validation, we induced corneal epithelial cell (HCECs) damage using 1 µg/mL benzalkonium chloride. METHODS: Fifteen male crossbred dogs were randomly divided into five groups: normal, dry eye self-healing control, cyclosporine-treated, ADMSC-CMV-treated and ADMSC-OESPARC-treated. HCECs were divided into four groups: normal control group, untreated model group, ADMSC-CMV supernatant culture group and ADMSC-OESRARC supernatant culture group. RESULTS: SPARC-modified ADMSC had the most significant effect on canine ocular surface inflammation, corneal injury, and tear recovery, and the addition of ADMSC-OESPARC cell supernatant also had a salvage effect on HCECs cellular damage, such as cell viability and cell proliferation ability. Moreover, analysis of the co-transcriptome sequencing data showed that SPARC could promote corneal epithelial cell repair by enhancing the in vitro viability, migration and proliferation and immunosuppression of ADMSC. CONCLUSION: The in vitro cell test and in vivo model totally suggest that the combination of SPARC and ADMSC has a promising future in novel dry eye therapy.


Assuntos
Compostos de Benzalcônio , Modelos Animais de Doenças , Síndromes do Olho Seco , Células-Tronco Mesenquimais , Osteonectina , Animais , Cães , Compostos de Benzalcônio/farmacologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Síndromes do Olho Seco/terapia , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/metabolismo , Síndromes do Olho Seco/patologia , Osteonectina/metabolismo , Osteonectina/genética , Masculino , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos
2.
Front Nutr ; 11: 1423305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962442

RESUMO

Background: Cumulative evidence has suggested that vitamin D deficiency is related with an increased susceptibility to various types of cancers. However, the association between vitamin D and thyroid cancer (TC) has remained to be unknown. Thus, there has been an urgent need for a meta-analysis to summarize existing evidence on vitamin D levels and the risk of TC. Objective: This meta-analysis aimed to figure out the association between vitamin D level and the risk of TC. Methods: A systematic search was performed for eligible articles on the association between vitamin D and TC based on PubMed, Embase, Web of Science, Cochrane, and ClinicalTrials.gov. Outcomes were the vitamin D level of cases with TC and the incidence of vitamin D deficiency in cases with TC comparing with the controls. The effect measures included standardized mean difference (SMD), ratio of means (RoM), and odds ratio (OR). A dose-response meta-analysis was performed to assess the correlation between vitamin D level and the risk of TC. Subgroup analyses and meta-regressions were conducted to explore the source of heterogeneity. And publication bias was evaluated through Begg's and Egger's tests. Results: Results of the meta-analysis revealed lower levels of vitamin D in TC cases comparing with those in control [SMD = -0.25, 95% CI: (-0.38, -0.12); RoM = 0.87, 95% CI: (0.81, 0.94)] and the levels of 1,25 (OH)D in cases with TC were also lower than controls [SMD = -0.49, 95% CI: (-0.80, -0.19); RoM = 0.90, 95% CI: (0.85, 0.96)]. And vitamin D deficiency was associated with the increased risk of TC [OR = 1.49, 95% CI: (1.23, 1.80)]. Additionally, results from the dose-response meta-analysis showed that there is a 6% increase in the risk of TC for each 10 ng/ml decrease in 25 (OH)D levels [OR = 0.94; 95% CI: (0.89, 0.99)]. Conclusions: Individuals with TC had lower levels of vitamin D compared to controls, and vitamin D deficiency was correlated with an increase risk of TC. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=504417, identifier: CRD42024504417.

3.
Stem Cell Res ; 79: 103496, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39018827

RESUMO

The KCNQ1 gene encodes a voltage-gated potassium channel required for cardiac action potentials. Mutations in this gene have been associated with hereditary long QT syndrome 1, Jervell and Lange-Nielsen syndromes, and familial atrial fibrillation. The NM_000218.3(KCNQ1): c.604 + 2T > C mutation has been categorized as the causative variant leading to LQT1. In this study, we generated a KCNQ1 (c.644 + 2T > C) mutation human embryonic stem cell line WAe009-A-1L based on CRISPR base editing system. WAe009-A-1L cell has the potential to differentiate cardiomyocytes and would be used as an in vitro disease model for mechanism exploration and drug screening.

4.
Anal Chem ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023129

RESUMO

Single-dispersed atoms (SDAs) as catalysts have drawn extensive attention due to their ultimate atom utilization efficiency and desirable catalytic capability. Atomic clusters (ACs) with potential multiple enzyme-like activities also display great practicability in catalysis-based biosensing. In this work, hybrid Mn ACs/SDAs were implanted in the frameworks of defect-engineered MIL 101(Cr) modulated by excess acetic acid, with a high loading capability of 13.9 wt %. Distinctively, Mn SDAs display weak superoxide dismutase (SOD)-like activity for specifically eliminating superoxide anion (O2•-), while Mn ACs/SDAs display both catalase-like and SOD-like activities for remarkable elimination of total reactive oxygen species (ROS) due to the cooperative effect of the two atom-scale catalytic sites. Thus, Mn ACs/SDAs can efficiently inhibit the chemiluminescent (CL) emission of multiple ROS-mediated luminol systems with a superior quenching rate of 85.5%. To validate the practicability of Mn ACs/SDAs for a sensitive CL assay, an immunoassay method was established to detect acetamiprid by using Mn ACs/SDAs as signal quenchers, which displayed a quantification range of 10 pg mL-1-25 ng mL-1 and a detection limit of 3.3 pg mL-1. This study paves an avenue for developing ACs/SDAs with multiple antioxidant activities that are suitable for application in biosensing.

5.
JAMA Netw Open ; 7(6): e2418460, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38941096

RESUMO

Importance: Air pollution is a recognized risk factor associated with chronic diseases, including respiratory and cardiovascular conditions, which can lead to physical and cognitive impairments in later life. Although these losses of function, individually or in combination, reduce individuals' likelihood of living independently, little is known about the association of air pollution with this critical outcome. Objective: To investigate associations between air pollution and loss of independence in later life. Design, Setting, and Participants: This cohort study was conducted as part of the Environmental Predictors Of Cognitive Health and Aging study and used 1998 to 2016 data from the Health and Retirement Study. Participants included respondents from this nationally representative, population-based cohort who were older than 50 years and had not previously reported a loss of independence. Analyses were performed from August 31 to October 15, 2023. Exposures: Mean 10-year pollutant concentrations (particulate matter less than 2.5 µm in diameter [PM2.5] or ranging from 2.5 µm to 10 µm in diameter [PM10-2.5], nitrogen dioxide [NO2], and ozone [O3]) were estimated at respondent addresses using spatiotemporal models along with PM2.5 levels from 9 emission sources. Main Outcomes and Measures: Loss of independence was defined as newly receiving care for at least 1 activity of daily living or instrumental activity of daily living due to health and memory problems or moving to a nursing home. Associations were estimated with generalized estimating equation regression adjusting for potential confounders. Results: Among 25 314 respondents older than 50 years (mean [SD] baseline age, 61.1 [9.4] years; 11 208 male [44.3%]), 9985 individuals (39.4%) experienced lost independence during a mean (SD) follow-up of 10.2 (5.5) years. Higher exposure levels of mean concentration were associated with increased risks of lost independence for total PM2.5 levels (risk ratio [RR] per 1-IQR of 10-year mean, 1.05; 95% CI, 1.01-1.10), PM2.5 levels from road traffic (RR per 1-IQR of 10-year mean, 1.09; 95% CI, 1.03-1.16) and nonroad traffic (RR per 1-IQR of 10-year mean, 1.13; 95% CI, 1.03-1.24), and NO2 levels (RR per 1-IQR of 10-year mean, 1.05; 95% CI, 1.01-1.08). Compared with other sources, traffic-generated pollutants were most consistently and robustly associated with loss of independence; only road traffic-related PM2.5 levels remained associated with increased risk after adjustment for PM2.5 from other sources (RR per 1-IQR increase in 10-year mean concentration, 1.10; 95% CI, 1.00-1.21). Other pollutant-outcome associations were null, except for O3 levels, which were associated with lower risks of lost independence (RR per 1-IQR increase in 10-year mean concentration, 0.94; 95% CI, 0.92-0.97). Conclusions and Relevance: This study found that long-term exposure to air pollution was associated with the need for help for lost independence in later life, with especially large and consistent increases in risk for pollution generated by traffic-related sources. These findings suggest that controlling air pollution could be associated with diversion or delay of the need for care and prolonged ability to live independently.


Assuntos
Poluição do Ar , Exposição Ambiental , Material Particulado , Humanos , Masculino , Idoso , Feminino , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Material Particulado/análise , Material Particulado/efeitos adversos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Estudos de Coortes , Ozônio/análise , Ozônio/efeitos adversos , Vida Independente/estatística & dados numéricos , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/efeitos adversos , Idoso de 80 Anos ou mais , Fatores de Risco
7.
Acta Biomater ; 182: 139-155, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38750914

RESUMO

Additively manufactured (AM) biodegradable zinc (Zn) alloys have recently emerged as promising porous bone-substituting materials, due to their moderate degradation rates, good biocompatibility, geometrically ordered microarchitectures, and bone-mimicking mechanical properties. While AM Zn alloy porous scaffolds mimicking the mechanical properties of trabecular bone have been previously reported, mimicking the mechanical properties of cortical bone remains a formidable challenge. To overcome this challenge, we developed the AM Zn-3Mg alloy. We used laser powder bed fusion to process Zn-3Mg and compared it with pure Zn. The AM Zn-3Mg alloy exhibited significantly refined grains and a unique microstructure with interlaced α-Zn/Mg2Zn11 phases. The compressive properties of the solid Zn-3Mg specimens greatly exceeded their tensile properties, with a compressive yield strength of up to 601 MPa and an ultimate strain of >60 %. We then designed and fabricated functionally graded porous structures with a solid core and achieved cortical bone-mimicking mechanical properties, including a compressive yield strength of >120 MPa and an elastic modulus of ≈20 GPa. The biodegradation rates of the Zn-3Mg specimens were lower than those of pure Zn and could be adjusted by tuning the AM process parameters. The Zn-3Mg specimens also exhibited improved biocompatibility as compared to pure Zn, including higher metabolic activity and enhanced osteogenic behavior of MC3T3 cells cultured with the extracts from the Zn-3Mg alloy specimens. Altogether, these results marked major progress in developing AM porous biodegradable metallic bone substitutes, which paved the way toward clinical adoption of Zn-based scaffolds for the treatment of load-bearing bony defects. STATEMENT OF SIGNIFICANCE: Our study presents a significant advancement in the realm of biodegradable metallic bone substitutes through the development of an additively manufactured Zn-3Mg alloy. This novel alloy showcases refined grains and a distinctive microstructure, enabling the fabrication of functionally graded porous structures with mechanical properties resembling cortical bone. The achieved compressive yield strength and elastic modulus signify a critical leap toward mimicking the mechanical behavior of load-bearing bone. Moreover, our findings reveal tunable biodegradation rates and enhanced biocompatibility compared to pure Zn, emphasizing the potential clinical utility of Zn-based scaffolds for treating load-bearing bony defects. This breakthrough opens doors for the wider adoption of zinc-based materials in regenerative orthopedics.


Assuntos
Ligas , Osso Cortical , Zinco , Ligas/química , Ligas/farmacologia , Zinco/química , Zinco/farmacologia , Animais , Camundongos , Osso Cortical/efeitos dos fármacos , Porosidade , Magnésio/química , Magnésio/farmacologia , Teste de Materiais , Força Compressiva , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Implantes Absorvíveis , Módulo de Elasticidade , Linhagem Celular
8.
J Acoust Soc Am ; 155(5): 2959-2972, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717203

RESUMO

Frequency hopping (FH) signals have been widely used to improve performance against frequency selective fading phenomenon of underwater channels. However, the channel is slowly varying in regard to changes in weather conditions, and thus the conventional FH detection transmitting signals with fixed frequency cannot guarantee good detection performance in the dynamic underwater environment. To overcome the performance degradation in slowly-varying fading dispersive channels, this paper proposes an adaptive frequency-hopping (AFH) target detection method. Compared with conventional FH detection methods, the AFH can adaptively select the optimal detection frequency based on premeasured background noise and channel frequency response measured from previous experiments. Numerical simulations and lake trials are conducted to verify the effectiveness of the AFH. The simulation results show that the AFH has better detection performance than the conventional FH. The lake trial results have also verified the validity and feasibility of AFH. Importantly, AFH also achieves a better output signal-to-noise ratio under actual noise interference.

9.
Int J Colorectal Dis ; 39(1): 83, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809459

RESUMO

BACKGROUND: Programmed cell death receptor 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are important immune checkpoint molecules that contribute to tumor immune evasion. However, the main treatment modalities for patients with early and intermediate stage colorectal cancer (CRC) are surgery, and the role of PD-1/PD-L1 inhibitors in these patients is not yet clear. Therefore, this study aims to review the treatment progress of PD-1/PD-L1 inhibitors for early- and intermediate-stage microsatellite high-instability (MSI-H) and stable (MSS) colorectal cancer, in order to provide more options for patients with early- and intermediate-stage colorectal cancer. MATERIALS AND METHODS: A scoping review of clinical trial registries ( Clinicaltrials.gov and EU clinical trial registers) and PubMed/Medline database of trials on PD-1/PD-L1 Inhibitors for early and middle-stage MSI-H and MSS CRC was done up to March 2024. RESULTS: A total of 19 trials related to early to mid-stage MSH-I or MSS CRC were included. Among them, 6 trials are in recruiting status, 3 trials are in active, not recruiting status, 3 trials are completed, 1 trial is terminated, and 1 trial is unknown. Of these, 9 trials involve MSI-H type CRC, and 10 trials involve MSS type CRC. Preclinical phase I/II trials are predominant, with only 3 clinical phase III trials. In trials related to MSI-H type CRC, 4 studies involve PD-1/PD-L1 inhibitors combined with neoadjuvant therapy, and 5 studies involve combination therapy. In trials related to MSS type CRC, 3 studies involve PD-1/PD-L1 inhibitors combined with targeted therapy, 2 studies involve PD-1/PD-L1 inhibitors combined with chemotherapy, 1 study involves PD-1/PD-L1 inhibitor combined immunotherapy, 1 study involves PD-1/PD-L1 inhibitors combined with bacterial therapy, and 3 studies involve PD-1/PD-L1 inhibitors combined with comprehensive therapy. As for primary outcome measures, 4 trials select pathological complete response rates, 3 trials select progression-free survival rate, 3 trials select objective response rate, 3 trials select overall survival rate, 4 trials select disease-free survival rate, 1 trial selects clinical complete response rate, and 1 trial selects percentage of participants with a dose-limiting toxicity. CONCLUSION: For early- and middle-stage MSI-H and MSS CRC, PD-1/PD-L1 inhibitors have shown some therapeutic efficacy, as evidenced by phase I/II studies. However, contemporary trial designs exhibit heterogeneity, with relatively few inclusion criteria, the use of various drug combinations and regimens, and significant variations in reported endpoints. Nevertheless, more double-arm, multicenter, randomized controlled trials are still needed to confirm the efficacy of immunotherapy.


Assuntos
Antígeno B7-H1 , Neoplasias Colorretais , Inibidores de Checkpoint Imunológico , Instabilidade de Microssatélites , Estadiamento de Neoplasias , Receptor de Morte Celular Programada 1 , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Antígeno B7-H1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico
10.
Stem Cell Res ; 77: 103425, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38653148

RESUMO

The KCNQ1 gene encodes a voltage-gated potassium channel, which plays an important role in the repolarization of myocardial action potentials. Mutations in this gene often result in type 1 long QT syndrome (LQT1). Here, we generated a KCNQ1 (c.1032 + 2 T > C) mutant human embryonic stem cell line (WAe009-A-1D) based on the transient expression adenine base editing system that converts base A to G. The WAe009-A-1D cell maintains the morphology, pluripotency, and normal karyotype of the stem cells and is capable of differentiating into all three germ layers in vivo.


Assuntos
Edição de Genes , Células-Tronco Embrionárias Humanas , Canal de Potássio KCNQ1 , Humanos , Canal de Potássio KCNQ1/genética , Canal de Potássio KCNQ1/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Linhagem Celular , Sistemas CRISPR-Cas , Diferenciação Celular , Mutação
11.
J Agric Food Chem ; 72(15): 8674-8683, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38569079

RESUMO

The enhancement of intracellular glutamate synthesis in glutamate-independent poly-γ-glutamic acid (γ-PGA)-producing strains is an essential strategy for improving γ-PGA production. Bacillus tequilensis BL01ΔpgdSΔggtΔsucAΔgudB:P43-ppc-pyk-gdhA for the efficient synthesis of γ-PGA was constructed through expression of glutamate synthesis features of Corynebacterium glutamicum, which increased the titer of γ-PGA by 2.18-fold (3.24 ± 0.22 g/L) compared to that of B. tequilensis BL01ΔpgdSΔggtΔsucAΔgudB (1.02 ± 0.11 g/L). To further improve the titer of γ-PGA and decrease the production of byproducts, three enzymes (Ppc, Pyk, and AceE) were assembled to a complex using SpyTag/Catcher pairs. The results showed that the γ-PGA titer of the assembled strain was 31.31% higher than that of the unassembled strain. To further reduce the production cost, 25.73 ± 0.69 g/L γ-PGA with a productivity of 0.48 g/L/h was obtained from cheap molasses. This work provides new metabolic engineering strategies to improve the production of γ-PGA in B. tequilensis BL01. Furthermore, the engineered strain has great potential for the industrial production of γ-PGA from molasses.


Assuntos
Bacillus , Corynebacterium glutamicum , Ácido Poliglutâmico/análogos & derivados , Ácido Glutâmico/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo
12.
PeerJ Comput Sci ; 10: e1977, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660191

RESUMO

Emotional recognition is a pivotal research domain in computer and cognitive science. Recent advancements have led to various emotion recognition methods, leveraging data from diverse sources like speech, facial expressions, electroencephalogram (EEG), electrocardiogram, and eye tracking (ET). This article introduces a novel emotion recognition framework, primarily targeting the analysis of users' psychological reactions and stimuli. It is important to note that the stimuli eliciting emotional responses are as critical as the responses themselves. Hence, our approach synergizes stimulus data with physical and physiological signals, pioneering a multimodal method for emotional cognition. Our proposed framework unites stimulus source data with physiological signals, aiming to enhance the accuracy and robustness of emotion recognition through data integration. We initiated an emotional cognition experiment to gather EEG and ET data alongside recording emotional responses. Building on this, we developed the Emotion-Multimodal Fusion Neural Network (E-MFNN), optimized for multimodal data fusion to process both stimulus and physiological data. We conducted extensive comparisons between our framework's outcomes and those from existing models, also assessing various algorithmic approaches within our framework. This comparison underscores our framework's efficacy in multimodal emotion recognition. The source code is publicly available at https://figshare.com/s/8833d837871c78542b29.

13.
Natl Sci Rev ; 11(5): nwae091, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38577671

RESUMO

Relaxation processes are crucial for understanding the structural rearrangements of liquids and amorphous materials. However, the overarching principle that governs these processes across vastly different materials remains an open question. Substantial analysis has been carried out based on the motions of individual particles. Here, as an alternative, we propose viewing the global configuration as a single entity. We introduce a global order parameter, namely the inherent structure minimal displacement (IS Dmin), to quantify the variability of configurations by a pattern-matching technique. Through atomic simulations of seven model glass-forming liquids, we unify the influences of temperature, pressure and perturbation time on the relaxation dissipation, via a scaling law between the mechanical damping factor and IS Dmin. Fundamentally, this scaling reflects the curvature of the local potential energy landscape. Our findings uncover a universal origin of glassy relaxation and offer an alternative approach to studying disordered systems.

14.
Dev Comp Immunol ; 157: 105169, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38522714

RESUMO

Janus kinases (JAKs) are important components of the JAK-STAT signaling pathway and play vital roles in innate immunity, autoimmune diseases, and inflammation. However, information about JAKs remains largely unknown in the spotted seabass, a fish species of Perciformes with great commercial value in the aquaculture industry. The aims of this study are to obtain the complete cDNA sequences of JAKs (JAK1, JAK2A, JAK2B, JAK3 and TYK2) from spotted seabass and to investigate their roles upon stimulation with lipopolysaccharides (LPS) and Edwardsiella tarda, using RT-PCR, PCR and qRT-PCR methods. All five JAK genes from the spotted seabass, each encode more than 1100 amino acids residues. JAK1 and JAK3 consist of 24 exons and 23 introns, whereas JAK2A, JAK2B and TYK2 consist of 23 exons and 22 introns. Furthermore, these five spotted seabass JAKs share high sequence identities with those of other fish species in protein domain analysis, synteny analysis, and phylogenetic analysis. Moreover, these five JAK genes were ubiquitously expressed in all tissues examined from healthy fish, and inducible expressions of JAKs were observed in the intestine, gill, head kidney, and spleen following LPS treatment or E. tarda infection. These findings indicate that all these JAK genes are involved in the antibacterial immunity of the spotted seabass and provide a basis for further understanding the mechanism of JAKs antibacterial response in the spotted sea bass.


Assuntos
Bass , Clonagem Molecular , Proteínas de Peixes , Janus Quinases , Lipopolissacarídeos , Filogenia , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Bass/genética , Bass/imunologia , Lipopolissacarídeos/imunologia , Janus Quinases/metabolismo , Janus Quinases/genética , Edwardsiella tarda/fisiologia , Imunidade Inata/genética , Doenças dos Peixes/imunologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/veterinária , Sequência de Aminoácidos
15.
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
16.
Int J Radiat Oncol Biol Phys ; 119(4): 1222-1233, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38266782

RESUMO

PURPOSE: Radioresistance of lung cancer poses a significant challenge when it comes to the treatment of advanced, recurrent, and metastatic cases. Ovarian tumor domain ubiquitin aldehyde binding 1 (OTUB1) is a key member of the deubiquitinase OTU superfamily. This protein is involved in various cellular functions, including cell proliferation, iron death, lipid metabolism, and cytokine secretion as well as immune response processes. However, its specific role and molecular mechanism in lung cancer radioresistance remain to be clarified. METHODS AND MATERIALS: The expression levels of OTUB1 in paired lung cancer tissues were determined by immunohistochemistry. In vitro and in vivo experiments were conducted to investigate the impact of OTUB1 on the growth and proliferation of lung cancer. Coimmunoprecipitation and Western blotting techniques were performed to examine the interaction between OTUB1 and CHK1. The DNA damage response was measured by comet tailing and immunofluorescence staining. KEGG pathways and Gene Ontology terms were analyzed based on RNA sequencing. RESULTS: Our findings reveal a high frequency of OTUB1 overexpression, which is associated with an unfavorable prognosis in patients with lung cancer. Through comprehensive investigations, we demonstrate that OTUB1 depletion impairs the process of DNA damage repair and overcomes radioresistance. In terms of the underlying mechanism, our study uncovers that OTUB1 deubiquitinates and stabilizes CHK1, which enhances CHK1 stability, thereby regulating DNA damage and repair. Additionally, we identify CHK1 as the primary downstream effector responsible for mediating the functional effects exerted by OTUB1 specifically in lung cancer. Importantly, OTUB1 has the potential to be a valuable marker for improving the efficacy of radiation therapy for lung adenocarcinoma. CONCLUSIONS: These findings unveil a novel role for OTUB1 in enhancing radioresistance by deubiquitination and stabilization of the expression of CHK1 in lung cancer and indicate that targeting OTUB1 holds great potential as an effective therapeutic approach for enhancing the efficacy of radiation therapy in lung cancer.


Assuntos
Quinase 1 do Ponto de Checagem , Progressão da Doença , Neoplasias Pulmonares , Tolerância a Radiação , Ubiquitinação , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Quinase 1 do Ponto de Checagem/metabolismo , Humanos , Animais , Linhagem Celular Tumoral , Camundongos , Proliferação de Células , Reparo do DNA , Cisteína Endopeptidases/metabolismo , Dano ao DNA , Proteases Específicas de Ubiquitina/metabolismo , Feminino , Camundongos Nus , Enzimas Desubiquitinantes/metabolismo , Estabilidade Proteica
17.
Clin Res Cardiol ; 113(5): 761-769, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38197895

RESUMO

BACKGROUND: Whether heart failure with preserved ejection fraction (HFpEF) is associated with an increased risk of developing systolic dysfunction and a poor prognosis in hypertrophic cardiomyopathy (HCM) patients is unknown. OBJECTIVE: We aimed to assess risk factors for the development of end-stage (ES) heart failure (HF) (ejection fraction < 50%) and compare the prognosis of different HF phenotypes. METHODS: This retrospective study was conducted on patients with HCM in China between January 2009 and February 2023. Patients were stratified into three different groups: HCM-non-HF, HCM-HFpEF and HCM-heart failure with reduced ejection fraction (HCM-HFrEF). The primary outcome was a composite of major adverse cardiac events (MACEs), including all-cause deaths, HF hospitalization, sudden cardiac death and ventricular tachycardia. RESULTS: Of 3,620 HCM patients enrolled, 1,553 (42.9%) had non-HF, 1,666 (46.0%) had HFpEF, and 579 patients (11.1%) had HFrEF at baseline. During the median follow-up period of 4.0 years (IQR 1.4-9.4 years), patients with HCM-HFpEF exhibited a higher incidence of ES-HF than those with HCM-non-HF (12.4% vs. 2.7%, P < 0.001). HFpEF was an independent risk factor for ES-HF development (HR 3.84, 2.54-5.80, P < 0.001). MACEs occurred in 26.9% with a higher incidence in HCM-HFpEF than HCM-non-HF (36.6% vs 12.2%, P < 0.001). HFpEF was an independent predictor of MACEs (HR 2.13, 1.75-2.59, P < 0.001). CONCLUSIONS: HFpEF is common in HCM. Compared to non-HF, it increases the risk of LVEF decline and poor prognosis. It may aid in risk stratification and need close echocardiography follow-up.


Assuntos
Cardiomiopatia Hipertrófica , Insuficiência Cardíaca , Humanos , Volume Sistólico , Estudos Retrospectivos , Prognóstico , Cardiomiopatia Hipertrófica/complicações , Função Ventricular Esquerda
18.
Geriatr Gerontol Int ; 24 Suppl 1: 88-95, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38013169

RESUMO

AIM: Cerium oxide, particularly in nanoparticle form (nanoceria), has been investigated for biomedical applications as a promising new agent for treating several pathologies. The aim of the present study was to characterize the pharmacologic effects of nanoceria in an animal model of chronic kidney disease. METHODS: We created the chronic kidney disease animal model by feeding rats a 0.25% adenine diet. Male Wistar rats were divided into five groups: normal diet, 0.25% adenine diet, or adenine diet containing three different doses or durations of nanoceria treatment. Blood was collected weekly from the tail veins of each rat and analyzed for renal function markers. After 5 weeks, various biochemical markers in serum, plasma, and urine were also analyzed. RESULTS: In the adenine-treated group, body weight was significantly decreased, and the kidneys lost much of their healthy reddish color and became lumpy and white in appearance. In addition, levels of serum creatinine, blood urea nitrogen, and plasma uremic toxins were significantly increased in adenine-treated rats compared with controls. Renal functional and structural damage in adenine diet model rats tended to be ameliorated by nanoceria ingestion. The high-dose cerium-treated group maintained reddish areas in the kidneys, and the increases in biomarker levels of creatinine, blood urea nitrogen, and inorganic phosphorus were markedly reduced, regardless of treatment duration. CONCLUSIONS: Ingestion of nanoceria may be effective for improving or preventing renal damage caused by adenine. Geriatr Gerontol Int 2024; 24: 88-95.


Assuntos
Cério , Nanopartículas , Insuficiência Renal Crônica , Ratos , Masculino , Animais , Ratos Wistar , Adenina/efeitos adversos , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/tratamento farmacológico , Cério/efeitos adversos , Biomarcadores , Creatinina , Modelos Animais de Doenças
19.
Artigo em Inglês | MEDLINE | ID: mdl-38090870

RESUMO

Most conventional crowd counting methods utilize a fully-supervised learning framework to establish a mapping between scene images and crowd density maps. They usually rely on a large quantity of costly and time-intensive pixel-level annotations for training supervision. One way to mitigate the intensive labeling effort and improve counting accuracy is to leverage large amounts of unlabeled images. This is attributed to the inherent self-structural information and rank consistency within a single image, offering additional qualitative relation supervision during training. Contrary to earlier methods that utilized the rank relations at the original image level, we explore such rank-consistency relation within the latent feature spaces. This approach enables the incorporation of numerous pyramid partial orders, strengthening the model representation capability. A notable advantage is that it can also increase the utilization ratio of unlabeled samples. Specifically, we propose a Deep Rank-consistEnt pyrAmid Model (), which makes full use of rank consistency across coarse-to-fine pyramid features in latent spaces for enhanced crowd counting with massive unlabeled images. In addition, we have collected a new unlabeled crowd counting dataset, FUDAN-UCC, comprising 4000 images for training purposes. Extensive experiments on four benchmark datasets, namely UCF-QNRF, ShanghaiTech PartA and PartB, and UCF-CC-50, show the effectiveness of our method compared with previous semi-supervised methods. The codes are available at https://github.com/bridgeqiqi/DREAM.

20.
PLoS One ; 18(11): e0292841, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37939045

RESUMO

Bitcoin is a decentralized digital cryptocurrency. Its network is a Peer-to-peer(P2P) network consisting of distributed nodes. Some of these nodes are always online and in this article are called Bitcoin backbone nodes. They have a significant impact on the stability and security of the Bitcoin network, so it is meaningful to analyze and discuss them. In this paper, we first continuously collect information about Bitcoin nodes from July 2021 through June 2022 (which is the longest duration of data collection to date). In total, we collect information on 127,613 Bitcoin nodes. At the same time, we conclude that the fluctuation of Bitcoin nodes is directly related to the fluctuation of onion network nodes. Further, we filtered 2694 Bitcoin backbone nodes based on our algorithm. By analyzing the backbone nodes' attributes such as geographic distribution, client version, operator, node function, and abnormal port number, it is demonstrated that these nodes are centralized and play an important role in the Bitcoin network. Based on this, three unsupervised machine learning algorithms are selected to cluster multiple attributes of backbone nodes in a more scientific way. In this paper, the whole process from data collection to cluster analysis is completed and the best results are obtained by comparison. The experiments proved the existence of centralization of Bitcoin backbone nodes and obtained the number of nodes within each cluster. Finally, cluster nodes are de-anonymized based on the optimal results. Through our experiments, we obtain organizational information about the deployers of 103 nodes, linking the Bitcoin backbone nodes to the real world, thus accurately demonstrating the existence of Bitcoin centrality.


Assuntos
Algoritmos , Humanos , Análise por Conglomerados , Coleta de Dados
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