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1.
Cell ; 176(6): 1477-1489.e14, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30827683

RESUMO

Receptor clustering on the cell membrane is critical in the signaling of many immunoreceptors, and this mechanism has previously been attributed to the extracellular and/or the intracellular interactions. Here, we report an unexpected finding that for death receptor 5 (DR5), a receptor in the tumor necrosis factor receptor superfamily, the transmembrane helix (TMH) alone in the receptor directly assembles a higher-order structure to drive signaling and that this structure is inhibited by the unliganded ectodomain. Nuclear magnetic resonance structure of the TMH in bicelles shows distinct trimerization and dimerization faces, allowing formation of dimer-trimer interaction networks. Single-TMH mutations that disrupt either trimerization or dimerization abolish ligand-induced receptor activation. Surprisingly, proteolytic removal of the DR5 ectodomain can fully activate downstream signaling in the absence of ligand. Our data suggest a receptor activation mechanism in which binding of ligand or antibodies to overcome the pre-ligand autoinhibition allows TMH clustering and thus signaling.


Assuntos
Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Células HEK293 , Humanos , Ligantes , Modelos Moleculares , Mutagênese Sítio-Dirigida/métodos , Ligação Proteica , Proteólise , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/química , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/ultraestrutura , Transdução de Sinais
2.
Mol Ther ; 32(2): 490-502, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38098228

RESUMO

Inadequate T cell activation has severely limited the success of T cell engager (TCE) therapy, especially in solid tumors. Enhancing T cell activity while maintaining the tumor specificity of TCEs is the key to improving their clinical efficacy. However, currently, there needs to be more effective strategies in clinical practice. Here, we design novel superantigen-fused TCEs that display robust tumor antigen-mediated T cell activation effects. These innovative drugs are not only armed with the powerful T cell activation ability of superantigens but also retain the dependence of TCEs on tumor antigens, realizing the ingenious combination of the advantages of two existing drugs. Superantigen-fused TCEs have been preliminarily proven to have good (>30-fold more potent) and specific (>25-fold more potent) antitumor activity in vitro and in vivo. Surprisingly, they can also induce the activation of T cell chemotaxis signals, which may promote T cell infiltration and further provide an additional guarantee for improving TCE efficacy in solid tumors. Overall, this proof-of-concept provides a potential strategy for improving the clinical efficacy of TCEs.


Assuntos
Neoplasias , Linfócitos T , Humanos , Superantígenos/uso terapêutico , Antígenos de Neoplasias , Morte Celular
3.
Biochem Biophys Res Commun ; 737: 150467, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39133984

RESUMO

In general, Cu(II) is the critical factor in catalyzing reactive oxygen species (ROS) production and accelerating amyloid-ß (Aß) oligomer formation in Alzheimer's disease (AD). Natural chelating agents with good biocompatibility and appropriate binding affinity with Cu(II) have emerged as potential candidates for AD therapy. Herein, we tested the capability of guluronic acid disaccharide (Di-GA), a natural chelating agent with the moderate association affinity to Cu(II), in inhibiting ROS production and Aß oligomer formation. The results showed that Di-GA was capable of chelating with Cu(II) and reducing ROS production, even in solutions containing Fe(II), Zn(II), and Aß. In addition, Di-GA can also capture Cu(II) from Cu-Aß complexes and decrease Aß oligomer formation. The cellular results confirmed that Di-GA prevented SH-SY5Y cells from ROS and Aß oligomer damage by reducing the injury of ROS and Aß oligomers on cell membrane and decreasing their intracellular damage on mitochondria. Notably, the slightly higher efficiency of Di-GA in chelating with Cu(I) than Cu(II) can be benefit for its in vivo applications, as Cu(I) is not only the most active but also the special intermediate specie during ROS production process. All of these results proved that Di-GA could be a promising marine drug candidate in reducing copper-related ROS damage and Aß oligomer toxicity associated with AD.

4.
BMC Plant Biol ; 24(1): 714, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060979

RESUMO

BACKGROUND: Festuca kryloviana is a significant native grass species in the Qinghai Lake region, and its low emergence rate is a primary factor limiting the successful establishment of cultivated grasslands. The region's arid and low-rainfall climate characteristics result in reduced soil moisture content at the surface. Despite the recognized impact of water availability on plant growth, the specific role of moisture in seedling development remains not fully elucidated. This study aims to investigate the germination rate and seedling growth velocity of F. kryloviana seeds under varying moisture conditions, and to integrate physiological and transcriptomic analyses of seedlings under these conditions to reveal the mechanisms by which water influences seedling development. RESULTS: The emergence rate of F. kryloviana seedlings exhibited an initial increase followed by a decrease with increasing moisture content. The highest emergence rate, reaching 75%, was observed under 20% soil moisture conditions. By the eighth day of the experiment, the lengths of the plumules and radicles under the optimal emergence rate (full water, FW) were 21.82% and 10.87% longer, respectively, than those under closely matching the soil moisture content during the background survey (stress water, SW). The differential development of seedlings under varying moisture regimes is attributed to sugar metabolism within the seeds and the accumulation of abscisic acid (ABA). At FW conditions, enhanced sugar metabolism, which generates more energy for seedling development, is facilitated by higher activities of α-amylase, sucrose synthase, and trehalose-6-phosphate synthase compared to SW conditions. This is reflected at the transcriptomic level with upregulated expression of the α-amylase (AMY2) gene and trehalose-6-phosphate synthase (TPS6), while genes associated with ABA signaling and transduction are downregulated. Additionally, under FW conditions, the expression of genes related to the chloroplast thylakoid photosystems, such as photosystem II (PSII) and photosystem I (PSI), is upregulated, enhancing the seedlings' light-capturing ability and photosynthetic efficiency, thereby improving their autotrophic capacity. Furthermore, FW treatment enhances the expression of the non-enzymatic antioxidant system, promoting metabolism within the seeds. In contrast, SW treatment increases the activity of the enzymatic antioxidant system, including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), to cope with water stress. CONCLUSIONS: Our experiment systematically evaluated the impact of moisture conditions on the growth and development of F. kryloviana seedlings. Physiological and transcriptomic data collectively indicate that adequate water (20%) supply enhances seedling growth and development by reducing ABA levels and increasing α-amylase activity within seeds, thereby boosting sugar metabolism and promoting the growth of seedling, which in turn leads to an improved emergence rate. Considering water management in future cultivation practices may be a crucial strategy for enhancing the successful establishment of F. kryloviana in grassland ecosystems.


Assuntos
Festuca , Plântula , Água , Plântula/crescimento & desenvolvimento , Plântula/genética , Plântula/metabolismo , Festuca/genética , Festuca/crescimento & desenvolvimento , Festuca/metabolismo , Água/metabolismo , Transcriptoma , Germinação , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismo
5.
Small ; : e2408688, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39410729

RESUMO

The electrochemical activation of inert CO2 molecules through C─C coupling reactions under ambient conditions remains a significant challenge but holds great promise for sustainable development and the reduction of CO2 emission. Lewis pairs can capture and react with CO2, offering a novel strategy for the electrosynthesis of high-value-added C2 products. Herein, an electron-beam irradiation strategy is presented for rapidly synthesizing a metal-organic framework (MOF) with well-defined Lewis pairs (i.e., Cu- Npyridinic). The synthesized MOFs exhibit a total C2 product faradic efficiency of 70.0% at -0.88 V versus RHE. In situ attenuated total reflection Fourier transform infrared and Raman spectra reveal that the electron-deficient Lewis acidic Cu sites and electron-rich Lewis basic pyridinic N sites in the ligand facilitate the targeted chemisorption, activation, and conversion of CO2 molecules. DFT calculations further elucidate the electronic interactions of key intermediates in the CO2 reduction reaction. The work not only advances Lewis pair-site MOFs as a new platform for CO2 electrochemical conversion, but also provides pioneering insights into the underlying mechanisms of electron-beam irradiated synthesis of advanced nanomaterials.

6.
J Med Virol ; 96(1): e29360, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38178597

RESUMO

Human papillomavirus (HPV) infection can lead to HPV-related cancer in men, including the anus, penile, and oropharyngeal cancers and precancerous lesions. This study retrospectively investigated HPV prevalence and genotype distribution in Liaocheng men between 2016 and 2022. The total HPV positive rate was 64.87% (2388/3681, 95% confidence interval [CI]: 63.32%-66.40%), where high risk (HR)-HPV and low risk (LR)-HPV accounted for 42.49% (1564/3681, 95% CI: 40.90%-44.09%) and 69.71% (2566/3681, 95% CI: 68.20%-71.17%), respectively. The mixed HPV infection rate of two and more genotypes was 35.72%. The infection rate of HR-HPV increased with the number of positive cases annually from 2016 (16.91%) to 2022 (46.59%). The most common HR-HPV genotypes were HPV16 (11.60%), HPV52 (6.95%), and HPV59 (6.28%), whereas the least common HR-HPV was HPV26. The most common LR-HPV genotypes were HPV6 (56.99%), HPV11 (23.79%), and HPV43 (6.37%). The 9 v HPV vaccine preventable for LR-HPV and HR-HPV accounted for 80.78% and 30.40%, respectively, in this study. Most HPV-positive patients aged 1-86 were in the 30-39 age group. This study confirmed that HPV prevalence in Liaocheng men was common and diverse. HPV16, HPV52, and HPV59 are widely distributed in Liaocheng men, and the male HR-HPV infection rate remained high in this region. Regarding public health and cancer prevention, it is recommended and effective to include the HPV vaccination in the national vaccination program for men.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Masculino , Adulto , Prevalência , Estudos Retrospectivos , Papillomavirus Humano 18 , Papillomaviridae/genética , Papillomavirus Humano 16/genética , Genótipo
7.
AIDS Care ; : 1-14, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39224077

RESUMO

Intervention mapping (IM) is a planning approach that reflects the intricate decision-making process involved in the design of behavior interventions. The development and implementation of IM is complex in preventing HIV/AIDS transmission. Therefore, it is significant to conduct a perfect preliminary work to successfully implement HIV/AIDS prevention. The objectives of this review were to collect and evaluate the data of the first three steps using IM to prevent HIV/AIDS transmission, and summarize the key points in the preliminary steps of IM. A total of 18 studies were identified, and six studies completely described the tasks in the first three steps of IM. Three studies described the logic model of the problem (n = 3). Six studies reported the matrix of behavior changes (n = 6), including personal and environmental determinants. Among the selected determinants, most studies reported the personal level determinants (self-efficacy and skills, knowledge, attitudes, and norms). The most used practical applications in reducing HIV/AIDS risk behaviors were video roles (n = 8) and role-model stories (n = 5). The review may be helpful for healthcare professionals to carefully design and implement the key procedures of the first three steps of the IM programs for people with HIV/AIDS in preventing HIV/AIDS transmission.

8.
BMC Infect Dis ; 24(1): 24, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166829

RESUMO

BACKGROUND: The first local outbreak of Delta Variant B.1.617.2 COVID-19 of China occurred in Guangzhou city, south China, in May 2021. This study analyzed the transmission chains and local cluster characteristics of this outbreak, intended to provide information support for the development and adjustment of local prevention and control strategies. METHODS: The transmission chains and local cluster characteristics of 161 local cases in the outbreak were described and analyzed. Incubation period, serial interval and generation time were calculated using the exact time of exposure and symptom onset date of the cases. The daily number of reported cases and the estimated generation time were used to estimate the effective reproduction number (Rt). RESULTS: We identified 7 superspreading events who had more than 5 next generation cases and their infected cases infected 70.81%(114/161) of all the cases transmission. Dining and family exposure were the main transmission routes in the outbreak, with 29.19% exposed through dining and 32.30% exposed through family places. Through further analysis of the outbreak, the estimated mean incubation period was 4.22 (95%CI: 3.66-4.94) days, the estimated mean generation time was 2.60 (95%CI: 1.96-3.11) days, and the estimated Rt was 3.29 (95%CI: 2.25-5.07). CONCLUSIONS: Classification and dynamically adjusted prevention and control measures had been carried out according to analysis of transmission chains and epidemical risk levels, including promoting nucleic acid screening at different regions and different risk levels, dividing closed-off area, controlled area according to the risk of infection, raising the requirements of leaving Guangzhou. By the above control measures, Guangzhou effectively control the outbreak within 28 days without implementing a large-scale lockdown policy.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2/genética , Controle de Doenças Transmissíveis , Surtos de Doenças , China/epidemiologia
9.
Mol Biol Rep ; 51(1): 755, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874707

RESUMO

BACKGROUND: Cataract contributes to visual impairment worldwide, and diabetes mellitus accelerates the formation and progression of cataract. Here we found that the expression level of miR-204-5p was diminished in the lens epithelium with anterior lens capsule of cataract patients compared to normal donors, and decreased more obviously in those of diabetic cataract (DC) patients. However, the contribution and mechanism of miR-204-5p during DC development remain elusive. METHODS AND RESULT: The mitochondrial membrane potential (MMP) was reduced in the lens epithelium with anterior lens capsule of DC patients and the H2O2-induced human lens epithelial cell (HLEC) cataract model, suggesting impaired mitochondrial functional capacity. Consistently, miR-204-5p knockdown by the specific inhibitor also attenuated the MMP in HLECs. Using bioinformatics and a luciferase assay, further by immunofluorescence staining and Western blot, we identified IGFBP5, an insulin-like growth factor binding protein, as a direct target of miR-204-5p in HLECs. IGFBP5 expression was upregulated in the lens epithelium with anterior lens capsule of DC patients and in the HLEC cataract model, and IGFBP5 knockdown could reverse the mitochondrial dysfunction in the HLEC cataract model. CONCLUSIONS: Our results demonstrate that miR-204-5p maintains mitochondrial functional integrity through repressing IGFBP5, and reveal IGFBP5 may be a new therapeutic target and prognostic factor for DC.


Assuntos
Catarata , Complicações do Diabetes , Células Epiteliais , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina , MicroRNAs , Mitocôndrias , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Catarata/genética , Catarata/metabolismo , Catarata/patologia , Mitocôndrias/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Células Epiteliais/metabolismo , Complicações do Diabetes/genética , Complicações do Diabetes/metabolismo , Potencial da Membrana Mitocondrial , Cristalino/metabolismo , Cristalino/patologia , Masculino , Feminino , Pessoa de Meia-Idade
10.
Environ Res ; 250: 118554, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38417657

RESUMO

Accurate prediction and measurement of yield stress are crucial for optimizing sludge treatment and disposal. However, the differences and applicability of various methods for measuring yield stress are subjects of ongoing debate. Meanwhile, literature on measuring sludge yield stress is limited to low solid concentrations (TS <10%), understanding and studying the yield stress of medium to high solid concentration sludge is crucial due to increasingly stringent standards for sludge treatment and disposal. So, this study employed a rotational rheometer to measure sludge yield stress across a wide range of TS (4-50%) using steady shear, dynamic oscillatory shear, and transient shear. The study derived significant conclusions by comparing and summarizing the applicability and limitations of each testing method: Dynamic oscillatory shear methods, including G'-σ curve method, γ-σ curve method, and G**γc method can measure sludge yield stress ranging from 4% to 40% TS, while other methods are restricted to low or limited solid concentrations; The G' = G″ method, utilizing the intersection of G' and G″ curves, consistently yields the highest value for yield stress when 4%≤ TS ≤ 12%; The rotational rheometer cannot measure sludge yield stress when the solid concentration exceeds 40% TS; The relationship between sludge yield stress and solid concentration is stronger as a power-law for TS ≤ 25%, transitioning to linear for higher concentrations (28%≤ TS <40%). This study systematically explores the applicability and limitations of various measurement methods for characterizing sludge yield stress across a wide range of solid concentrations, providing valuable guidance for scientific measurement and highlighting challenging research issues.


Assuntos
Esgotos , Reologia/métodos , Eliminação de Resíduos Líquidos/métodos
11.
BMC Public Health ; 24(1): 494, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365650

RESUMO

BACKGROUND: Quantitative evidence on the impact of meteorological factors on influenza transmissibility across different virus types/subtypes is scarce, and no previous studies have reported the effect of hourly temperature variability (HTV) on influenza transmissibility. Herein, we explored the associations between meteorological factors and influenza transmissibility according to the influenza type and subtype in Guangzhou, a subtropical city in China. METHODS: We collected influenza surveillance and meteorological data of Guangzhou between October 2010 and December 2019. Influenza transmissibility was measured using the instantaneous effective reproductive number (Rt). A gamma regression with a log link combined with a distributed lag non-linear model was used to assess the associations of daily meteorological factors with Rt by influenza types/subtypes. RESULTS: The exposure-response relationship between ambient temperature and Rt was non-linear, with elevated transmissibility at low and high temperatures. Influenza transmissibility increased as HTV increased when HTV < around 4.5 °C. A non-linear association was observed between absolute humidity and Rt, with increased transmissibility at low absolute humidity and at around 19 g/m3. Relative humidity had a U-shaped association with influenza transmissibility. The associations between meteorological factors and influenza transmissibility varied according to the influenza type and subtype: elevated transmissibility was observed at high ambient temperatures for influenza A(H3N2), but not for influenza A(H1N1)pdm09; transmissibility of influenza A(H1N1)pdm09 increased as HTV increased when HTV < around 4.5 °C, but the transmissibility decreased with HTV when HTV < 2.5 °C and 3.0 °C for influenza A(H3N2) and B, respectively; positive association of Rt with absolute humidity was witnessed for influenza A(H3N2) even when absolute humidity was larger than 19 g/m3, which was different from that for influenza A(H1N1)pdm09 and influenza B. CONCLUSIONS: Temperature variability has an impact on influenza transmissibility. Ambient temperature, temperature variability, and humidity influence the transmissibility of different influenza types/subtypes discrepantly. Our findings have important implications for improving preparedness for influenza epidemics, especially under climate change conditions.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Influenza Humana/epidemiologia , Vírus da Influenza A Subtipo H3N2 , Conceitos Meteorológicos , Temperatura , Umidade , China/epidemiologia
12.
Molecules ; 29(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257388

RESUMO

A new approach is presented in this paper for the dynamic modeling of the chemical and isotopic evolution of C1-3 during the hydrocarbon generation process. Based on systematic data obtained from published papers for the pyrolysis of various hydrocarbon sources (type I kerogen/source rock, type II kerogen/source rock, type III kerogen/source rock, crude oil, and asphalt, etc.), the empirical evolution framework of the chemical and isotopic composition of C1-3 during the hydrocarbon generation process was built. Although the empirical framework was built only by fitting a large amount of pyrolysis data, the chemical and isotopic composition of C1-3 derived from the pyrolysis experiments all follow evolution laws, convincing us that it is applicable to the thermal evolution process of various hydrocarbon sources. Based on the simplified formula of the isotopic composition of mixed natural gas at different maturities (δ13Cmixed), δ13Cmixed = X×niA×δ13CiA+Y×niB×δ13CiBX×niA+Y×niB, it can be derived that the cumulative isotopic composition of alkane generated in a certain maturity interval can be expressed by the integral of the product of the instantaneous isotopic composition and instantaneous yield at a certain maturity point, and then divided by the cumulative yield of alkane generated in the corresponding maturity interval. Thus, the cumulative isotopic composition (A(X)), cumulative yield (B(X)), instantaneous isotope (C(X)), and instantaneous yield (D(x)) in the dynamic model, comply with the following formula during the maturity interval of (X0~X). A(X) = ∫X0XCX×DXdxB(X), where A(X) and B(X) can be obtained by the fitting of pyrolysis data, and D(x) can also be obtained from the derivation of B(X). The dynamic model was applied on the pyrolysis data of Pingliang Shale to illustrate the quantitative evolution of the cumulative yield, instantaneous yield, cumulative isotope, and instantaneous isotope of C1-3 with increasing maturity. The dynamic model can quantify the yield of methane, ethane, and propane, as well as δ13C1, δ13C2, and δ13C3, respectively, during the hydrocarbon generation process. This model is of great significance for evaluating the natural gas resources of hydrocarbon source rock of different maturities and for identifying the origin and evolutionary process of hydrocarbons by chemical and isotopic data. Moreover, this model provides an approach to study the dynamic evolution of the isotope series of C1-3 (including reversed isotopic series), which is promising for revealing the mechanism responsible for isotopic reversal when combined with post-generation studies.

13.
Molecules ; 29(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38893486

RESUMO

Understanding the optimal extraction methods for flavonoids from Abelmoschus manihot flowers (AMF) is crucial for unlocking their potential benefits. This study aimed to optimize the efficiency of flavonoid extraction from AMF. After comparing extraction methods, the ultrasonic cell crusher demonstrated superior performance over conventional techniques. Four key factors-solid-to-liquid ratio (1:10 to 1:50 g·mL-1), ethanol concentration (55% to 95%), ultrasonic time (10 to 50 min), and ultrasonic power (5% to 25% of 900 W)-were investigated and normalized using the entropy weight method. This led to a comprehensive evaluation (CE). Optimization of extraction conditions for the ultrasonic cell crusher was achieved through response surface methodology and a deep neural network model, resulting in optimal parameters: ethanol volume fraction of 66%, solid-to-liquid ratio of 1:21 g/mL, extraction efficiency of 9%, and extraction duration of 35 min, yielding a CE value of 23.14 (RSD < 1%). Additionally, the inhibitory effects of the optimized extracts against Streptococcus mutans (S. mutans) were assessed. The results revealed that AMF extract (AMFE) exhibits inhibitory effects on S. mutans, with concomitant inhibition of sucrase and lactate dehydrogenase (LDH). The MIC of AMFE against planktonic S. mutans is 3 mg/mL, with an MBC of 6 mg/mL. Within the concentration range of 1/8 MIC to 2 MIC of AMFE, the activities of sucrase and LDH decreased by 318.934 U/mg prot and 61.844 U/mg prot, respectively. The antioxidant activity of AMFE was assessed using the potassium ferricyanide reduction and phosphomolybdenum methods. Additionally, the effect of AMFE on DPPH, ABTS, and ·OH free radical scavenging abilities was determined. The concentrations at which AMFE exhibited over 90% scavenging rate for ABTS and DPPH free radicals were found to be 0.125 mg/mL and 2 mg/mL, respectively.


Assuntos
Abelmoschus , Antioxidantes , Flavonoides , Flores , Redes Neurais de Computação , Extratos Vegetais , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Abelmoschus/química , Flores/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Ondas Ultrassônicas
14.
J Sci Food Agric ; 104(9): 5186-5196, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38288747

RESUMO

BACKGROUND: Tannic acid (TA), a naturally occurring polyphenol, has shown diverse potential in preventing intestinal damage in piglet diarrhea induced by Enterotoxigenic Escherichia coli (ETEC) K88. However, the protective effect of TA on ETEC k88 infection-induced post-weaning diarrhea and its potential mechanism has not been well elucidated. Therefore, an animal trial was carried out to investigate the effects of dietary supplementation with TA on the intestinal diarrhea of weaned piglets challenged with ETEC K88. In addition, porcine intestinal epithelial cells were used as an in vitro model to explore the mechanism through which TA alleviates intestinal oxidative damage and inflammation. RESULTS: The results indicated that TA supplementation (2 and 4 g kg-1) reduced diarrhea rate, enzyme activity (diamine oxidase [DAO] and Malondialdehyde [MAD]) and serum inflammatory cytokines concentration (TNF-α and IL-1ß) (P < 0.05) compared to the Infection group (IG), group in vivo. In vitro, TA treatment effectively alleviated ETEC-induced cytotoxicity, increased the expression of ZO-1, occludin and claudin-1 at both mRNA and protein levels. Moreover, TA pre-treatment increased the activity of antioxidant enzymes (such as T-SOD) and decreased serum cytokine levels (TNF-α and IL-1ß). Furthermore, TA increased cellular antioxidant capacity by activating the Nrf2 signaling pathway and decreased inflammatory response by down-regulating the expression of TLR4, MyD88, NF-kB and NLRP3. CONCLUSION: The present study showed that TA reduced the diarrhea rate of weaned piglets by restoring the intestinal mucosal mechanical barrier function, alleviating oxidative stress and inflammation. The underlying mechanism was achieved by modulating the p62-keap1-Nrf2 and TLR4-NF-κB-NLRP3 pathway. © 2024 Society of Chemical Industry.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Proteína 1 Associada a ECH Semelhante a Kelch , Fator 2 Relacionado a NF-E2 , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transdução de Sinais , Taninos , Receptor 4 Toll-Like , Animais , Suínos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , NF-kappa B/metabolismo , NF-kappa B/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Taninos/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Linhagem Celular , Transdução de Sinais/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/metabolismo , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Polifenóis
15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(8): 1010-1015, 2024 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-39097288

RESUMO

DNA methylation is an important epigenetic regulatory mechanism which plays a crucial role in cell differentiation and development. Its function is closely related to DNA methyltransferase 3 alpha (DNMT3A), which can affect gene expression and stem cell differentiation. The mutation rate of the DNMT3A gene is relatively high in Acute myeloid leukemia (AML), but its type and pathogenic mechanism are not yet clear. Further research on DNMT3A may help to identify its pathogenic targets and provide a basis for precise treatment of AML. This article has provided a review for the research progress on the expression of the DNMT3A gene in AML.


Assuntos
DNA (Citosina-5-)-Metiltransferases , DNA Metiltransferase 3A , Leucemia Mieloide Aguda , DNA (Citosina-5-)-Metiltransferases/genética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/enzimologia , Metilação de DNA , Regulação Leucêmica da Expressão Gênica
16.
Chin J Traumatol ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39179446

RESUMO

Spinal intradural (subdural and subarachnoid) hematoma following percutaneous kyphoplasty is an extremely rare complication. In this report, we described a case of 2 episodes of subarachnoid hemorrhage with delayed paralysis after kyphoplasty. A 73-year-old man underwent percutaneous kyphoplasty in our hospital an osteoporotic vertebral fracture at the T12 level. On the 55 h after kyphoplasty for T12 osteoporotic vertebral fracture, he developed paralysis of the lower limbs. An emergency posterior decompression from T8 to L2 was performed. And the subarachnoid hematomas were removed. Postoperatively, the neurological symptoms improved rapidly. However, 2 weeks after the operation, the patient experienced a setback with severe neurological decline (paraplegia with sensory and autonomic dysfunction). An emergency posterior decompression from T5 to L2 was performed. The subarachnoid hematomas were removed. This case reflects the cause and progression of spinal subdural hematoma. Previous literature has debated the best treatment approach for spinal subarachnoid hemorrhage, but the prognosis of patients is heavily dependent on precise symptom evaluation and localization.

17.
J Biol Chem ; 298(6): 101946, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35447114

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. However, the molecular mechanisms that promote dysregulation of hepatic triglyceride metabolism and lead to NAFLD are poorly understood, and effective treatments are limited. Leukemia inhibitory factor (LIF) is a member of the interleukin-6 cytokine family and has been shown to regulate a variety of physiological processes, although its role in hepatic triglyceride metabolism remains unknown. In the present study, we measured circulating LIF levels by ELISA in 214 patients with biopsy-diagnosed NAFLD as well as 314 normal control patients. We further investigated the potential role and mechanism of LIF on hepatic lipid metabolism in obese mice. We found that circulating LIF levels correlated with the severity of liver steatosis. Patients with ballooning, fibrosis, lobular inflammation, and abnormally elevated liver injury markers alanine transaminase and aspartate aminotransferase also had higher levels of serum LIF than control patients. Furthermore, animal studies showed that white adipose tissue-derived LIF could ameliorate liver steatosis through activation of hepatic LIF receptor signaling pathways. Together, our results suggested that targeting LIF-LIF receptor signaling might be a promising strategy for treating NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Fator Inibidor de Leucemia/sangue , Fator Inibidor de Leucemia/metabolismo , Fígado/patologia , Camundongos , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Triglicerídeos/metabolismo
18.
Plant Cell Environ ; 46(12): 3887-3901, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37656830

RESUMO

Alfalfa (Medicago sativa L.) is considered to be the most important forage crop on a global scale. Nevertheless, soil salinity significantly decreases productivity, seriously threatening food security worldwide. One viable strategy is to explore salt stress-responsive factors and elucidate their underlying molecular mechanism, and utilize them in further alfalfa breeding. In the present study, we designated MsWRKY33 as a representative salt stress-responsive factor preferentially expressed in alfalfa roots and leaves. Subsequently, it was demonstrated that MsWRKY33 was localized in the cell nucleus, and functioned as a transcriptional activator of the W-box element. Transgenic alfalfa overexpressing MsWRKY33 displayed enhanced salt stress tolerance and antioxidant activities with no significant difference in other agronomic traits. Transcriptome profiling of MsWRKY33 transgenic alfalfa under control and salt treatment unveiled significantly altered expression of reactive oxygen species (ROS) scavenger genes in transgenic alfalfa. Subsequent examination revealed that MsWRKY33 binded to the promoter of MsERF5, activating its expression and consequently fine-tuning the ROS-scavenging enzyme activity. Furthermore, MsWRKY33 interacted with the functional fragment of MsCaMBP25, which participates in Ca2+ signaling transduction. Collectively, this research offers new insight into the molecular mechanism of alfalfa salt stress tolerance and highlights the potential utility of MsWRKY33 in alfalfa breeding.


Assuntos
Medicago sativa , Tolerância ao Sal , Medicago sativa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Perfilação da Expressão Gênica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas
19.
Pharmacol Res ; 192: 106781, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37119880

RESUMO

Targeting single tumor antigens makes it difficult to provide sufficient tumor selectivity for T cell engagers (TCEs), leading to undesirable toxicity and even treatment failure, which is particularly serious in solid tumors. Here, we designed novel trispecific TCEs (TriTCEs) to improve the tumor selectivity of TCEs by logic-gated dual tumor-targeting. TriTCE can effectively redirect and activate T cells to kill tumor cells (∼18 pM EC50) by inducing the aggregation of dual tumor antigens, which was ∼70- or 750- fold more effective than the single tumor-targeted isotype controls, respectively. Further in vivo experiments indicated that TriTCE has the ability to accumulate in tumor tissue and can induce circulating T cells to infiltrate into tumor sites. Hence, TriTCE showed a stronger tumor growth inhibition ability and significantly prolonged the survival time of the mice. Finally, we revealed that this concept of logic-gated dual tumor-targeted TriTCE can be applied to target different tumor antigens. Cumulatively, we reported novel dual tumor-targeted TriTCEs that can mediate a robust T cell response by simultaneous recognition of dual tumor antigens at the same cell surface. TriTCEs allow better selective T cell activity on tumor cells, resulting in safer TCE treatment.


Assuntos
Neoplasias , Linfócitos T , Camundongos , Animais , Neoplasias/metabolismo , Antígenos de Neoplasias
20.
Nanotechnology ; 35(9)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38016442

RESUMO

Lithium-sulfur (Li-S) batteries have gained considerable attention for high theoretical specific capacity and energy density. However, their development is hampered by the poor electrical conductivity of sulfur and the shuttle of polysulfides. Herein, the acidified bamboo-structure carbon nanotubes (BCNTs) were mixed with polyvinylidene difluoride and pyrolyzed at high-temperature to obtain the fluorinated bamboo-structure carbon nanotubes (FBCNTs), which were compounded with sulfur as the cathode. The prepared S@FBCNTs with sulfur loading reaching 74.2 wt.% shows a high initial specific capacity of 1407.5 mAh·g-1at the discharge rate of 0.1 C. When the discharge rate was increased to 5 C, the capacity could be maintained at 622.3 mAh·g-1. The electrical conductivity of carbon nanotubes is effectively improved by semi-ionic C-F bonds formed by the doped F atoms and carbon atoms. Simultaneously, the surface of the F-containing carbon tubes exhibits strong polarity and strong chemisorption effect on polysulfides, which inhibits the shuttle effect of Li-S batteries.

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