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1.
Nature ; 595(7867): 361-369, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34262215

RESUMO

With the rapid growth and development of proton-exchange membrane fuel cell (PEMFC) technology, there has been increasing demand for clean and sustainable global energy applications. Of the many device-level and infrastructure challenges that need to be overcome before wide commercialization can be realized, one of the most critical ones is increasing the PEMFC power density, and ambitious goals have been proposed globally. For example, the short- and long-term power density goals of Japan's New Energy and Industrial Technology Development Organization are 6 kilowatts per litre by 2030 and 9 kilowatts per litre by 2040, respectively. To this end, here we propose technical development directions for next-generation high-power-density PEMFCs. We present the latest ideas for improvements in the membrane electrode assembly and its components with regard to water and thermal management and materials. These concepts are expected to be implemented in next-generation PEMFCs to achieve high power density.

2.
Inflamm Res ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896289

RESUMO

BACKGROUND: Tumor microenvironment (TME) heterogeneity is an important factor affecting the treatment response of immune checkpoint inhibitors (ICI). However, the TME heterogeneity of melanoma is still widely characterized. METHODS: We downloaded the single-cell sequencing data sets of two melanoma patients from the GEO database, and used the "Scissor" algorithm and the "BayesPrism" algorithm to comprehensively analyze the characteristics of microenvironment cells based on single-cell and bulk RNA-seq data. The prediction model of immunotherapy response was constructed by machine learning and verified in three cohorts of GEO database. RESULTS: We identified seven cell types. In the Scissor+ subtype cell population, the top three were T cells, B cells and melanoma cells. In the Scissor- subtype, there are more macrophages. By quantifying the characteristics of TME, significant differences in B cells between responders and non-responders were observed. The higher the proportion of B cells, the better the prognosis. At the same time, macrophages in the non-responsive group increased significantly. Finally, nine gene features for predicting ICI response were constructed, and their predictive performance was superior in three external validation groups. CONCLUSION: Our study revealed the heterogeneity of melanoma TME and found a new predictive biomarker, which provided theoretical support and new insights for precise immunotherapy of melanoma patients.

3.
BMC Infect Dis ; 24(1): 280, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438963

RESUMO

BACKGROUND: The causal association between gut microbiome and HIV infection remains to be elucidated. We conducted a two-sample mendelian randomization analysis to estimate the causality between gut microbiome and HIV infection. METHODS: Publicly released genome-wide association studies summary data were collected to perform the mendelian analysis. The GWAS summary data of gut microbiome was retrieved from the MiBioGen consortium, which contains 18 340 samples from 24 cohorts. GWAS summary data of HIV infection was collected from the R5 release of FinnGen consortium, including 357 HIV infected cases and 218 435 controls. The SNPs were selected as instrumental variables according to our selection rules. And SNPs with a F-statistics less than ten were regarded as weak instrumental variables and excluded. Mendelian randomization analysis was conducted by five methods, including inverse variance weighted (IVW), MR-Egger, weighted median, weighted mode, and simple mode. The Cochran's Q test and MR-Egger intercept test were performed to identify heterogeneity and pleiotropy. Leave-one-out analysis were used to test the sensitivity of the results. RESULTS: Fifteen gut microbiota taxa showed causal effects on HIV infection according to the MR methods. Four taxa were observed to increase the risk of HIV infection, including Ruminococcaceae (OR: 2.468[1.043, 5.842], P: 0.039), Ruminococcaceae UCG005 (OR: 2.051[1.048, 4.011], P: 0.036), Subdoligranulum (OR: 3.957[1.762, 8.887], P < 0.001) and Victivallis (OR: 1.605[1.012, 2.547], P=0.044). Erysipelotrichaceae was protective factor of HIV infection (OR: 0.278[0.106, 0.731], P < 0.001) and Methanobrevibacter was also found to be associated with reduced risk of HIV infection (OR: 0.509[0.265, 0.980], P=0.043). Horizontal pleiotropy was found for Fusicatenibacter (P<0.05) according to the MR-Egger regression intercept analysis. No heterogeneity was detected. CONCLUSION: Our results demonstrate significant causal effects of gut microbiome on HIV infection. These findings facilitate future studies to develop better strategies for HIV prophylaxis through gut microbiome regulation. Further explorations are also warranted to dissect the mechanism of how gut microbiome affects HIV susceptibility.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV , Humanos , Microbioma Gastrointestinal/genética , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Causalidade , Nonoxinol
4.
BMC Womens Health ; 24(1): 333, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849811

RESUMO

BACKGROUND: Pregnant women faced great challenges and psychological and physiological changes of varying degrees during the omicron epidemic outbreak. It is important to recognize the potential impact of these challenges on the mental health of pregnant women and to provide appropriate resources and support to mitigate their effects. METHOD: By using the convenience sampling approach, a total of 401 pregnant women from two hospitals of different grades in two cities were included in the survey. The cross-sectional survey was conducted by basic characteristics, Generalized Anxiety Disorder (GAD-7), Patient Health Questionnaire (PHQ-9), Insomnia Severity Index (ISI) and self-made questionnaire. RESULTS: Insomnia affected 207 participants (51.6%), depression affected 160 participants (39.9%) and anxiety affected 151 participants (37.7%). Moreover, pregnant women in provincial capital city were more likely to experience anxiety, depression and insomnia than those in county-level city (P < 0.01). Pregnant women's anxiety, depression and insomnia were positively correlated with the severity of COVID-19 infection (P < 0.05). However, COVID-19 infection had no appreciable impact on maternal demand for termination of pregnancy and cesarean section (P > 0.05). CONCLUSION: Pregnant women frequently suffer from anxiety disorder, depression and insomnia as a result of the omicron pandemic in China. During this period, the community and medical professionals should provide more psychological counseling, conduct health education and offer virtual prenatal care to pregnant women (particularly in the provincial capital city).


Assuntos
Ansiedade , COVID-19 , Depressão , Gestantes , Distúrbios do Início e da Manutenção do Sono , Humanos , Feminino , COVID-19/epidemiologia , COVID-19/psicologia , China/epidemiologia , Gravidez , Adulto , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Ansiedade/epidemiologia , Ansiedade/psicologia , Gestantes/psicologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Inquéritos e Questionários , Adulto Jovem , SARS-CoV-2 , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/psicologia , Saúde Mental/estatística & dados numéricos
5.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928496

RESUMO

The tumor microenvironment (TME) is crucial in tumor development, metastasis, and response to immunotherapy. DNA methylation can regulate the TME without altering the DNA sequence. However, research on the methylation-driven TME in clear-cell renal cell carcinoma (ccRCC) is still lacking. In this study, integrated DNA methylation and RNA-seq data were used to explore methylation-driven genes (MDGs). Immune scores were calculated using the ESTIMATE, which was employed to identify TME-related genes. A new signature connected with methylation-regulated TME using univariate, multivariate Cox regression and LASSO regression analyses was developed. This signature consists of four TME-MDGs, including AJAP1, HOXB9, MYH14, and SLC6A19, which exhibit high methylation and low expression in tumors. Validation was performed using qRT-PCR which confirmed their downregulation in ccRCC clinical samples. Additionally, the signature demonstrated stable predictive performance in different subtypes of ccRCC. Risk scores are positively correlated with TMN stages, immune cell infiltration, tumor mutation burden, and adverse outcomes of immunotherapy. Interestingly, the expression of four TME-MDGs are highly correlated with the sensitivity of first-line drugs in ccRCC treatment, especially pazopanib. Molecular docking indicates a high affinity binding between the proteins and pazopanib. In summary, our study elucidates the comprehensive role of methylation-driven TME in ccRCC, aiding in identifying patients sensitive to immunotherapy and targeted therapy, and providing new therapeutic targets for ccRCC treatment.


Assuntos
Carcinoma de Células Renais , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais , Microambiente Tumoral , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Humanos , Microambiente Tumoral/genética , Neoplasias Renais/genética , Neoplasias Renais/patologia , Pirimidinas/uso terapêutico , Indazóis/uso terapêutico , Indazóis/farmacologia , Sulfonamidas/uso terapêutico , Sulfonamidas/farmacologia , Biomarcadores Tumorais/genética , Feminino , Simulação de Acoplamento Molecular , Perfilação da Expressão Gênica/métodos , Masculino
6.
Can J Infect Dis Med Microbiol ; 2024: 9164605, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419669

RESUMO

Background: Medical staff in China faced great challenges and psychological and physiological changes of varying degrees during the omicron epidemic outbreak. It is important to recognize the potential impact of these challenges on the mental health of medical staff and to provide appropriate resources and support to mitigate their effects. Methods: A total of 354 medical staff in two obstetrics and gynecology hospitals of different grades were included in this survey using convenience sampling. The cross-sectional self-report questionnaires survey was conducted using the Basic Characteristics Questionnaire, Generalized Anxiety Disorder (GAD-7), Patient Health Questionnaire (PHQ-9), and Insomnia Severity Index (ISI). Results: There were 169 (47.7%) participants suffering from anxiety disorder. Working with fever, working in obstetrics, and working with protective clothing were the risk factors for anxiety in medical staff (p < 0.05). One hundred and ninety-six (55.4%) participants were depressed. Working with fever and working in obstetrics were the risk factors for depression in medical staff (p < 0.05). There were 117 (33.1%) participants suffering from insomnia. Working with fever, high educational level, and severe COVID-19 infection status were the risk factors for insomnia in medical staff (p < 0.05). Moreover, medical staff in a provincial hospital were more anxious and depressed than those in a county hospital. At last, there were more participants working with fever in obstetrics (p < 0.05). Conclusion: Anxiety disorder, depression, and insomnia were common among obstetrics and gynecology medical staff during the outbreak of omicron pandemic. During this period, more resources for psychological counselling should be provided to the hospital as well as more reasonable staffing arrangements, and working while having a fever is prohibited, especially in provincial hospital.

7.
BMC Genomics ; 24(1): 385, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430202

RESUMO

BACKGROUND: Identifying reliable biomarkers could effectively predict esophagus carcinoma (EC) patients with poor prognosis. In this work, we constructed an immune-related gene pairs (IRGP) signature to evaluate the prognosis of EC. RESULTS: The IRGP signature was trained by the TCGA cohort and validated by three GEO datasets, respectively. Cox regression model together with LASSO was applied to construct the overall survival (OS) associated IRGP. 21 IRGPs consisting of 38 immune-related genes were included in our signature, according to which patients were stratified into high- and low-risk groups. The results of Kaplan-Meier survival analyses indicated that high-risk EC patients had worse OS than low-risk group in the training set, meta-validation set and all independent validation datasets. After adjustment in multivariate Cox analyses, our signature continued to be an independent prognostic factor of EC and the signature-based nomogram could effectively predict the prognosis of EC sufferers. Besides, Gene Ontology analysis revealed this signature is related to immunity. 'CIBERSORT' analysis revealed the infiltration levels of plasma cells and activated CD4 memory T cells in two risk groups were significantly different. Ultimately, we validated the expression levels of six selected genes from IRGP index in KYSE-150 and KYSE-450. CONCLUSIONS: This IRGP signature could be applied to select EC patients with high mortality risk, thereby improving prospects for the treatment of EC.


Assuntos
Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/genética , Linfócitos T CD4-Positivos , Ontologia Genética , Estimativa de Kaplan-Meier , Análise Multivariada
8.
Int J Mol Sci ; 24(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37895143

RESUMO

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a poor prognosis. Increasing evidence highlights the significant role of immune-related genes (IRGs) in ACC progression and immunotherapy, but the research is still limited. Based on the Cancer Genome Atlas (TCGA) database, immune-related molecular subtypes were identified by unsupervised consensus clustering. Univariate Cox analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression were employed to further establish immune-related gene signatures (IRGS). An evaluation of immune cell infiltration, biological function, tumor mutation burden (TMB), predicted immunotherapy response, and drug sensitivity in ACC patients was conducted to elucidate the applicative efficacy of IRGS in precision therapy. ACC patients were divided into two molecular subtypes through consistent clustering. Furthermore, the 3-gene signature (including PRKCA, LTBP1, and BIRC5) based on two molecular subtypes demonstrated consistent prognostic efficacy across the TCGA and GEO datasets and emerged as an independent prognostic factor. The low-risk group exhibited heightened immune cell infiltration, TMB, and immune checkpoint inhibitors (ICIs), associated with a favorable prognosis. Pathways associated with drug metabolism, hormone regulation, and metabolism were activated in the low-risk group. In conclusion, our findings suggest IRGS can be used as an independent prognostic biomarker, providing a foundation for shaping future ACC immunotherapy strategies.


Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Humanos , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/terapia , Prognóstico , Análise por Conglomerados , Bases de Dados Factuais , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/terapia , Microambiente Tumoral
9.
Molecules ; 28(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37446733

RESUMO

The growth behavior, stability, electronic and magnetic properties of the Gd2Sin- (n = 3-12) clusters are reported, which are investigated using density functional theory calculations combined with the Saunders 'Kick' and the Artificial Bee Colony algorithm. The lowest-lying structures of Gd2Sin- (n = 3-12) are all exohedral structures with two Gd atoms face-capping the Sin frameworks. Results show that the pentagonal bipyramid (PB) shape is the basic framework for the nascent growth process of the present clusters, and forming the PB structure begins with n = 5. The Gd2Si5- is the potential magic cluster due to significantly higher average binding energies and second order difference energies, which can also be further verified by localized orbital locator and adaptive natural density partitioning methods. Moreover, the localized f-electron can be observed by natural atomic orbital analysis, implying that these electrons are not affected by the pure silicon atoms and scarcely participate in bonding. Hence, the implantation of these elements into a silicon substrate could present a potential alternative strategy for designing and synthesizing rare earth magnetic silicon-based materials.


Assuntos
Algoritmos , Silício , Proliferação de Células , Ciclo Celular , Elétrons
10.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499144

RESUMO

Auxin regulates plant growth and development, as well as helps plants to survive abiotic stresses, but the effects of auxin on the growth of alkaline-stressed rice and the underlying molecular and physiological mechanisms remain unknown. Through exogenous application of IAA/TIBA, this study explored the physiological and molecular mechanisms of alkaline stress tolerance enhancement using two rice genotypes. Alkaline stress was observed to damage the plant growth, while exogenous application of IAA mitigates the alkaline-stress-induce inhibition of plant growth. After application of exogenous IAA to alkaline-stressed rice, dry shoot biomass, foliar chlorophyll content, photosynthetic rate in the two rice genotypes increased by 12.6-15.6%, 11.7-40.3%, 51.4-106.6%, respectively. The adventitious root number, root surface area, total root length and dry root biomass in the two rice genotypes increased by 29.3-33.3%, 26.4-27.2%, 42.5-35.5% and 12.8-33.1%, respectively. The accumulation of H2O2, MAD were significantly decreased with the application of IAA. The activities of CAT, POD, and SOD in rice plants were significantly increased by exogenous application of IAA. The expression levels of genes controlling IAA biosynthesis and transport were significantly increased, while there were no significant effects on the gene expression that controlled IAA catabolism. These results showed that exogenous application of IAA could mitigate the alkaline-stress-induced inhibition of plant growth by regulating the reactive oxygen species scavenging system, root development and expression of gene involved in IAA biosynthesis, transport and catabolism. These results provide a new direction and empirical basis for improving crop alkaline tolerance with exogenous application of IAA.


Assuntos
Oryza , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Estresse Fisiológico , Clorofila/metabolismo , Raízes de Plantas
11.
Int J Mol Sci ; 23(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36233273

RESUMO

Although some biomarkers have been used to predict prognosis of lower-grade gliomas (LGGs), a pathway-related signature associated with immune response has not been developed. A key signaling pathway was determined according to the lowest adjusted p value among 50 hallmark pathways. The least absolute shrinkage and selection operator (LASSO) and stepwise multivariate Cox analyses were performed to construct a pathway-related gene signature. Somatic mutation, drug sensitivity and prediction of immunotherapy analyses were conducted to reveal the value of this signature in targeted therapies. In this study, an allograft rejection (AR) pathway was considered as a crucial signaling pathway, and we constructed an AR-related five-gene signature, which can independently predict the prognosis of LGGs. High-AR LGG patients had higher tumor mutation burden (TMB), Immunophenscore (IPS), IMmuno-PREdictive Score (IMPRES), T cell-inflamed gene expression profile (GEP) score and MHC I association immunoscore (MIAS) than low-AR patients. Most importantly, our signature can be validated in four immunotherapy cohorts. Furthermore, IC50 values of the six classic chemotherapeutic drugs were significantly elevated in the low-AR group compared with the high-AR group. This signature might be regarded as an underlying biomarker in predicting prognosis for LGGs, possibly providing more therapeutic strategies for future clinical research.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioma , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Glioma/genética , Glioma/metabolismo , Glioma/terapia , Humanos , Imunidade , RNA Mensageiro/genética
12.
Molecules ; 27(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080200

RESUMO

In this paper, two new iridium (III) complexes, [Ir(ppy)2(ipbp)](PF6) (Ir1) (ppy = 2-phenylpyridine, ipbp = 3-(1H-imidazo[4,5-f][1,10]phenanthrolin-2yl)-4H-chromen-4-one) and [Ir(bzq)2(ipbp)](PF6) (Ir2) (bzq = benzo[h]quinolone), were synthesized and characterized. The cytotoxicity of the complexes against human colon cancer HCT116 and normal LO2 cells was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The complexes Ir1 and Ir2 show high cytotoxic efficacy toward HCT116 cells with a low IC50 value of 1.75 ± 0.10 and 6.12 ± 0.2 µM. Interestingly, Ir1 only kills cancer cells, not normal LO2 cells (IC50 > 200 µM). The inhibition of cell proliferation and migration were investigated by multiple tumor spheroid (3D) and wound healing experiments. The cellular uptake was explored under a fluorescence microscope. The intracellular reactive oxygen species (ROS), change of mitochondrial membrane potential, glutathione (GSH) and adenine nucleoside triphosphate (ATP) were studied. Apoptosis and cell cycle arrest were performed by flow cytometry. The results show that the complexes induce early apoptosis and inhibit the cell proliferation at the G0/G1 phase. Additionally, the apoptotic mechanism was researched by Western blot analysis. The results obtained demonstrate that the complexes cause apoptosis in HCT116 cells through ROS-mediated mitochondrial dysfunction and the inhibition of PI3K/AKT signaling pathways.


Assuntos
Antineoplásicos , Neoplasias do Colo , Complexos de Coordenação , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Células HCT116 , Humanos , Irídio/farmacologia , Fosfatidilinositol 3-Quinases , Espécies Reativas de Oxigênio/metabolismo
13.
Cell Biol Int ; 45(6): 1296-1305, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33739578

RESUMO

The prognosis of advanced colorectal cancer (CRC) is currently still very poor, which suggests that the biological mechanisms of CRC oncogenesis are not fully understood. This study was conducted to explore the regulatory effect of SOX-17 on the expression of microRNA (miR)-302b-3p, and the involvement of SOX-17 in the invasion and apoptosis of CRC cells. The expression of SOX-17 and miR-302a,b,c,d-3p in colorectal cancer and normal colon epithelial cell lines was measured by real-time polymerase chain reaction and/or western blot. The regulatory effects of SOX-17 on miR-302b-3p gene in HT29 and LoVo cells were tested using the ChiP assay. The biological activities of SOX-17 and miR-302b-3p were evaluated by invasion and apoptosis assay. Results showed that transfection of SOX-17 small interfering RNA (siSOX-17) significantly increased, whereas transfection of SOX-17 overexpression vector (oeSOX-17) significantly decreased, miR-302b expression in HT29 and LoVo cells. Cotransfection of oeSOX-17 and miR-302b-3p inhibitor (INmiR-302b) significantly blocked the effects of SOX-17 in HT29 and LoVo cells. ChIP experiments showed that SOX-17 bonded to the miR-302b-3p promoter in HT29 and LoVo cells. Transfection of oeSOX-17 and miR-302b-3p mimics (MImiR-302b) significantly decreased, whereas transfection of siSOX-17 and INmiR-302b significantly increased, the invasion of HT29 and LoVo cells. In contrast, transfection of oeSOX-17 and MImiR-302b significantly increased, while transfection of siSOX-17 and INmiR-302b significantly decreased, apoptosis in HT29 and LoVo cells. Cotransfection of oeSOX-17 and INmiR-302b significantly blocked the effects of oeSOX-17 on cell invasion and apoptosis in HT29 and LoVo cells. These results suggested that SOX-17 can bind to the promoter of miR-302b-3p gene to regulate its expression, while both SOX-17 and miR-302b regulate the invasion and apoptosis in colorectal cancer cells.


Assuntos
Neoplasias Colorretais/metabolismo , MicroRNAs/fisiologia , Fatores de Transcrição SOXF/fisiologia , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos
14.
J Chem Phys ; 154(20): 204302, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241172

RESUMO

A systematic structure and property investigation of MnGen - (n = 3-14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen - (n = 3-10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12 - cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade-Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12 -. The spin density and natural population analysis indicate that MnGen - clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn.

15.
J Anim Physiol Anim Nutr (Berl) ; 105(5): 849-860, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33764632

RESUMO

Two trials were carried out to study the effects of copper sulphate (CuSO4 ) on detoxifying glucosinolates (GLS) in rapeseed cake (RSC) and compare the effects of feeding CuSO4 -treated and untreated RSC on nutrient digestion and nitrogen (N) metabolism in steers. In Trial 1, different concentrations of CuSO4 solution (1.6 vs. 3.2 g CuSO4 ·5H2 O L-1 ), soaking temperatures (25 vs. 60°C) and drying methods (air drying at 60°C vs. freeze drying) were allocated in a 2 × 2 × 2 factorial arrangement in vitro. In Trial 2, six steers and dietary inclusions of untreated RSC (control), CuSO4 -treated RSC and CuSO4 -added RSC were assigned in a replicated 3 × 3 Latin square design. CuSO4 treatment in vitro decreased the contents of GLS and thiocyanate (TC) in RSC (p < 0.001). The total amount of GLS and TC decreased by 62.7-68.5% for all treatments. The animal trial showed that CuSO4 -treated RSC inclusion decreased ruminal concentration of valerate (p < 0.01), whereas it did not affect ruminal pH, ammonia N and total volatile fatty acids. Compared with the control, feeding CuSO4 -treated or CuSO4 -added RSC had no effect on plasma concentrations of triiodothyronine and thyroxine, N excretion and N retention. CuSO4 -treated RSC tended to increase neutral detergent fibre digestibility (p = 0.072) and urinary excretion of urea (p = 0.056). Urinary excretion of purine derivatives (p = 0.076) and rumen microbial N supply (p = 0.084) tended to decrease when feeding CuSO4 -treated RSC versus control. TC was found to be the only metabolite of GLS in rumen fluid, plasma and urine. It was feasible to detoxify GLS in RSC using low CuSO4 at room temperature. However, feeding CuSO4 -treated or CuSO4 -added RSC had minor effects on rumen fermentation, nutrient digestion and N metabolism in steers. CuSO4 treatment on RSC for feeding steers seems to be unnecessary.


Assuntos
Brassica napus , Rúmen , Ração Animal/análise , Animais , Bovinos , Sulfato de Cobre/farmacologia , Dieta/veterinária , Digestão , Fermentação , Glucosinolatos/metabolismo , Glucosinolatos/farmacologia , Masculino , Nitrogênio/metabolismo , Nutrientes , Rúmen/metabolismo
16.
Appl Environ Microbiol ; 86(22)2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859601

RESUMO

Six steers were used to study the effects of dietary supplementation with sodium sulfate (Na2SO4) on rumen fermentation, nutrient digestion, rumen microbiota, and plasma metabolites. The animals were fed a basal ration with Na2SO4 added at 0 g/day (sulfur [S] content of 0.115% dry matter [DM]), 20 g/day (S at 0.185% DM), or 40 g/day (S at 0.255% DM) in a replicate 3-by-3 Latin square design. The results indicated that supplementing with Na2SO4 increased the ruminal concentration of total volatile fatty acids, the molar proportions of acetate and butyrate, the ruminal concentrations of microbial protein, SO42--S, and S2--S, and the digestibility of fiber, while it decreased the molar proportion of propionate and the ruminal concentration of ammonia nitrogen. Supplementing with Na2SO4 increased the diversity and the richness of rumen microbiota and the relative abundances of the phylum Firmicutes and genera Ruminococcus 2, Rikenellaceae RC9 gut group, and Desulfovibrio, whereas it decreased the relative abundances of the phylum Bacteroidetes and genera Prevotella 1, Prevotellaceae UCG-001, and Treponema 2 Supplementing with Na2SO4 also increased the plasma concentrations of amino acids (l-arginine, l-methionine, l-cysteine, and l-lysine), purine derivatives (xanthine and hypoxanthine), vitamins (thiamine and biotin), and lipids (acetylcarnitine and l-carnitine). It was concluded that supplementing the steer ration with Na2SO4 was beneficial for improving the rumen fermentation, fiber digestibility, and nutrient metabolism through modulating the rumen microbial community.IMPORTANCE Essential elements like nitrogen and sulfur greatly affect rumen fermentation and metabolism in ruminants. However, little knowledge is available on the effects of sulfur on the rumen microbiota and plasma metabolome. The results of the present trial demonstrated that supplementing the steer ration with sodium sulfate markedly improved rumen fermentation, fiber digestibility, and metabolism of amino acids, purine derivatives, and vitamins through effects on the ruminal microbiome. The facts obtained from the present trial clarified the possible mechanisms of the positive effects of sulfur on rumen fermentation and nutrient utilization.


Assuntos
Fibras na Dieta/metabolismo , Digestão , Microbioma Gastrointestinal/efeitos dos fármacos , Metaboloma , Rúmen/efeitos dos fármacos , Sulfatos/metabolismo , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais/análise , Fermentação , Masculino , Plasma/metabolismo , Rúmen/microbiologia , Rúmen/fisiologia , Sulfatos/administração & dosagem
17.
Neurochem Res ; 45(2): 322-330, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31773373

RESUMO

This study examined the activation of mitophagy following cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) and the relationship between the change with time and apoptosis. MAIN METHODS: The male Sprague-Dawley rats were randomized into four groups: Sham group, CPR24h group, CPR48h group, CPR72h group. The rat model of cardiac arrest was established by asphyxiation. We employed western blot to analyze the levels of mitophagy related proteins of hippocampus, JC-1 to detect mitochondrial membrane potential (MMP) and flow cytometry to measure the rate of apoptosis of hippocampal neurons. Moreover, we also intuitively observed the occurrence of mitophagy through electron microscopy. KEY FINDINGS: The results showed that the levels of TOMM20 and Tim23 protein were significantly decreased after CPR, which were more remarkable following 72 h of CPR. However, the protein levels of dynamin related protein 1 (Drp1) and cytochrome C (Cyt-c) were strongly up-regulated after CPR. Meanwhile, the hippocampal MMP decreased gradually with time after CPR. Furthermore, we more intuitively verified the activation of mitophagy through electron microscopy. In addition, the rats of apoptosis rate of hippocampus after CPR were significantly increased, which were gradually enhanced over time from 24 h until at least 72 h following CPR. SIGNIFICANCE: with the enhancement of mitophagy, the apoptosis of hippocampal neurons was gradually enhanced, which suggested mitophagy may be excessive activated and aggravating brain damage after CA and CPR.


Assuntos
Reanimação Cardiopulmonar/efeitos adversos , Parada Cardíaca/fisiopatologia , Hipocampo/metabolismo , Mitofagia/fisiologia , Animais , Apoptose/fisiologia , Parada Cardíaca/terapia , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Ratos Sprague-Dawley
18.
Cell Biol Int ; 44(7): 1514-1522, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32196848

RESUMO

Colorectal cancer (CRC) is an aggressive malignancy with a high incidence and mortality rate. Although a targeting therapy has been developed, the 5-year survival rate is still very low in CRC patients with distant metastasis. Thus, the identification of new targets is still significant for improving CRC treatment. Klotho is a tumor suppressor, and its expression is aberrant in CRC. In this study, the roles of the FLI-1 gene in regulating Klotho gene expression and Klotho-associated signaling, as well as the effects of FLI-1 on colony formation, invasion, and apoptosis were investigated in CRC cell lines. The methylation of the FLI-1 gene was analyzed using a commercial methylation kit. Results showed that FLI-1 messenger RNA and protein expression were downregulated in six CRC cell lines when compared with the normal colon mucosal epithelial cell line, which negatively correlated with the level of DNA methylation. Silencing of FLI-1 gene expression decreased Klotho protein expression and phosphorylation of ß-catenin protein at Thr41 /Ser45 , but increased Wnt3a and ß-catenin protein expression and IGF-1R phosphorylation in HT29 cells. In contrast to silencing FLI-1, overexpressing FLI-1 significantly increased Klotho protein expression and phosphorylation of ß-catenin protein at Thr41 /Ser45 , but decreased Wnt3a and ß-catenin protein expression and IGF-1R phosphorylation in Caco-2 cells. Silencing of FLI-1 gene expression significantly increased colony formation and invasion, but decreased apoptosis in HT29 cells. In contrast, overexpressing the FLI-1 gene significantly decreased colony formation and invasion, but increased apoptosis in Caco-2 cells. These findings suggest that FLI-1 functions as a tumor suppressor in CRC cells and positively regulates Klotho signaling. Hypermethylation may be one of the causes of the loss of FLI-1 gene expression in CRC cells.


Assuntos
Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Glucuronidase/metabolismo , Proteína Proto-Oncogênica c-fli-1/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias Colorretais/patologia , Genes Supressores de Tumor/fisiologia , Humanos , Proteínas Klotho , Via de Sinalização Wnt/fisiologia
19.
Cell Biol Int ; 44(10): 2011-2020, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32544287

RESUMO

The prognosis of advanced gastric cancer is poor and understanding the biology and subsequent development of new targeting therapy is still an urgent need. This study was conducted to explore the effect of BR2 (a 17-amino acid peptide)-SOX17 (human sex determining region Y (SRY)-related high-mobility group (HMG) box protein family member 17) fusion protein on Klotho gene expression in gastric cancer cells. The regulatory effects of SOX17 on Klotho gene in gastric cancer cells were tested using dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay. The therapeutic effects of BR2-SOX17 were evaluated by proliferation, colony formation, invasion assay, and cell apoptosis analysis. Results showed that SOX17 enhanced Klotho gene expression in gastric adenocarcinoma cells through binding to the promoter of Klotho gene. BR2-SOX17 fusion protein was effective in delivering SOX17 into gastric cancer cells and subsequently inhibited the cell proliferation, colony formation, and invasion, increased E-cadherin protein expression, decreased vimentin protein expression, as well as induced apoptosis. Our findings suggested SOX17 can bind to the promoter of Klotho gene to enhance Klotho gene expression in gastric cancer cells. The fused BR2-SOX17 protein is an effective agent for targeting therapy of gastric cancer.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glucuronidase/metabolismo , Fatores de Transcrição SOXF/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Klotho , Peptídeos/farmacologia , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão
20.
Neurocrit Care ; 32(3): 812-821, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31576483

RESUMO

BACKGROUND AND OBJECTIVE: Attenuation of neuronal apoptosis helps maintain neurological function in patients after cardiac arrest. After ischemia-reperfusion, both cyclosporin A (CsA) and ischemic postconditioning independently protect mitochondria and thus reduce nerve injury. This study employed a rat model to evaluate the neuroprotective effect of combining ischemic postconditioning with CsA after cardiopulmonary resuscitation (CPR). METHODS: Rats were apportioned equally to model control, postconditioned, CsA-treated, or CsA + postconditioned groups. Asphyxial cardiac arrest was imposed using modified Utstein-style guidelines. In the appropriate groups, postconditioning was implemented by ischemia and reperfusion (clamping and loosening the left femoral artery); CsA treatment was delivered with a single intravenous dose. Neurological deficits were scored at different times after CPR. Histological evaluation and electron microscopy were used to evaluate tissue damage, and TUNEL and flow cytometry were used to measure the apoptotic rate of hippocampal neurons and size of the mitochondrial permeability transition pore (mPTP) opening. RESULTS: The apoptotic rate was significantly lower in the postconditioned and CsA-treated groups compared with the model control and lowest in the CsA + postconditioned group. By histological evaluation and electron microscopy, the least damage was observed in the CsA + postconditioned group. The neurological deficit score of the CsA + postconditioned group was significantly higher than that of the CsA-treated group, but the size of the mPTP openings of these two groups was comparable. CONCLUSION: Ischemic postconditioning combined with CsA exerted a better neuroprotective effect after CPR than did either postconditioning or CsA alone. Inhibiting the opening of the mPTP is not the only neuroprotective mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Ciclosporina/farmacologia , Inibidores Enzimáticos/farmacologia , Pós-Condicionamento Isquêmico/métodos , Neurônios/efeitos dos fármacos , Síndrome Pós-Parada Cardíaca/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Encéfalo/efeitos dos fármacos , Reanimação Cardiopulmonar , Parada Cardíaca , Poro de Transição de Permeabilidade Mitocondrial/antagonistas & inibidores , Ratos
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