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1.
Plant J ; 117(4): 1115-1129, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37966861

RESUMEN

Nitrogen (N) is an essential nutrient for crop growth and development, significantly influencing both yield and quality. Melatonin (MT), a known enhancer of abiotic stress tolerance, has been extensively studied. However, its relationship with nutrient stress, particularly N deficiency, and the underlying regulatory mechanisms of MT on N absorption remain unclear. In this study, exogenous MT treatment was found to improve the tolerance of apple plants to N deficiency. Apple plants overexpressing the MT biosynthetic gene N-acetylserotonin methyltransferase 9 (MdASMT9) were used to further investigate the effects of endogenous MT on low-N stress. Overexpression of MdASMT9 improved the light harvesting and heat transfer capability of apple plants, thereby mitigating the detrimental effects of N deficiency on the photosynthetic system. Proteomic and physiological data analyses indicated that MdASMT9 overexpression enhanced the trichloroacetic acid cycle and positively modulated amino acid metabolism to counteract N-deficiency stress. Additionally, both exogenous and endogenous MT promoted the transcription of MdHY5, which in turn bound to the MdNRT2.1 and MdNRT2.4 promoters and activated their expression. Notably, MT-mediated promotion of MdNRT2.1 and MdNRT2.4 expression through regulating MdHY5, ultimately enhancing N absorption. Taken together, these findings shed light on the association between MdASMT9-mediated MT biosynthesis and N absorption in apple plants under N-deficiency conditions.


Asunto(s)
Malus , Melatonina , Melatonina/metabolismo , Malus/genética , Malus/metabolismo , Nitrógeno/metabolismo , Proteómica , Plantas Modificadas Genéticamente/genética
2.
J Virol ; 98(1): e0078923, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38168677

RESUMEN

Zika virus (ZIKV) infection caused neurological complications and male infertility, leading to the accumulation of antigen-specific immune cells in immune-privileged organs (IPOs). Thus, it is important to understand the immunological responses to ZIKV in IPOs. We extensively investigated the ZIKV-specific T cell immunity in IPOs in Ifnar1-/- mice, based on an immunodominant epitope E294-302 tetramer. The distinct kinetics and functions of virus-specific CD8+ T cells infiltrated into different IPOs were characterized, with late elevation in the brain and spinal cord. Single epitope E294-302-specific T cells can account for 20-60% of the total CD8+ T cells in the brain, spinal cord, and testicle and persist for at least 90 days in the brain and spinal cord. The E294-302-specific TCRαßs within the IPOs are featured with the majority of clonotypes utilizing TRAV9N-3 paired with diverse TRBV chains, but with distinct αß paired clonotypes in 7 and 30 days post-infection. Specific chemokine receptors, Ccr2 and Ccr5, were selectively expressed in the E294-302-specific CD8+ T cells within the brain and testicle, indicating an IPO-oriented migration of virus-specific CD8+ T cells after infection. Overall, this study adds to the understanding of virus-specific CD8+ T cell responses for controlling and clearing ZIKV infection in IPOs.IMPORTANCEThe immune-privileged organs (IPOs), such as the central nervous system and testicles, presented pathogenicity and inflammation after Zika virus (ZIKV) infection with infiltrated CD8+ T cells. Our data show that CD8+ T cells keep up with virus increases and decreases in immune-privileged organs. Furthermore, our study provides the first ex vivo comparative analyses of the composition and diversity related to TCRα/ß clonotypes across anatomical sites and ZIKV infection phases. We show that the vast majority of TCRα/ß clonotypes in tissues utilize TRAV9N-3 with conservation. Specific chemokine expression, including Ccr2 and Ccr5, was found to be selectively expressed in the E294-302-specific CD8+ T cells within the brain and testicle, indicating an IPO-oriented migration of the virus-specific CD8+ T cells after the infection. Our study adds insights into the anti-viral immunological characterization and chemotaxis mechanism of virus-specific CD8+ T cells after ZIKV infection in different IPOs.


Asunto(s)
Linfocitos T CD8-positivos , Privilegio Inmunológico , Infección por el Virus Zika , Animales , Masculino , Ratones , Encéfalo/inmunología , Encéfalo/virología , Linfocitos T CD8-positivos/inmunología , Receptor de Interferón alfa y beta/genética , Virus Zika , Infección por el Virus Zika/inmunología , Ratones Noqueados , Testículo/inmunología , Testículo/virología
3.
J Immunol ; 210(8): 1074-1085, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36897229

RESUMEN

Influenza A viruses (IAVs) and influenza B viruses (IBVs) cause annual epidemics in human populations with seasonal circulation spikes. Peptide AM58-66GL9 located at residues 58-66 of M1 protein of IAVs has been recognized as an immunodominant T cell epitope with HLA-A*0201 restriction and broadly used as a positive reference in influenza immunity. This peptide also almost completely overlaps with a nuclear export signal (NES) 59-68 in IAV M1, which explains the limited escape mutations under the T cell immune pressure in this region. In this study, we investigated the potential immunogenicity and NES in the corresponding region of IBV. The long peptide covering this region can be recognized by specific T cells and induce robust expression of IFN-γ among HLA-B*1501 donors in vivo, but not in HLA-A*0201 donors. Among a series of truncated peptides derived from this region, we identified an immunodominant HLA-B*1501-restricted T cell epitope BM58-66AF9 (ALIGASICF) in the M1 protein of IBV. Furthermore, the structure of the HLA-B*1501/BM58-66AF9 complex shows that BM58-66AF9 performs a flat and featureless conformation that is similar to AM58-66GL9 presented by HLA-A*0201. In contrast with IAV, the sequence around residues 55-70 of IBV M1 does not contain an NES. Our comparative study on IBVs and IAVs provides new insights into the immune and evolution characteristics of IBVs and may shed light on vaccine development for influenza viruses.


Asunto(s)
Virus de la Influenza A , Gripe Humana , Humanos , Animales , Señales de Exportación Nuclear , Epítopos de Linfocito T , Virus de la Influenza B , Antígenos HLA-B/genética , Estadios del Ciclo de Vida
4.
Plant Cell Environ ; 47(3): 751-764, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38164091

RESUMEN

High temperatures negatively impact the yield and quality of fruit crops. Exogenous melatonin (MT) application has been shown to enhance heat tolerance, but the response of endogenous MT to heat stress, particularly in perennial fruit trees, remains unclear. The present study investigated the effects of high temperatures on transgenic apple plants overexpressing the MT biosynthesis gene N-acetylserotonin methyltransferase 9 (MdASMT9). Endogenous MT protected transgenic plants from heat stress by increasing antioxidant enzyme activity and scavenging reactive oxygen species (ROS), and protecting the chloroplasts from damage. Application of MT and overexpression of MdASMT9 also reduced abscisic acid accumulation through promoting MdWRKY33-mediated transcriptional inhibition of MdNCED1 and MdNCED3, thus inducing stomatal opening for better heat dissipation. Furthermore, MT-enhanced autophagic activity through promoting MdWRKY33-mediated transcriptional enhancement of MdATG18a under heat stress. These findings provide new insights into the regulation of endogenous MT and its role in improving basal thermotolerance in perennial fruit trees.


Asunto(s)
Malus , Melatonina , Termotolerancia , Termotolerancia/genética , Melatonina/farmacología , Malus/genética , Antioxidantes/farmacología , Respuesta al Choque Térmico/genética , Plantas Modificadas Genéticamente/genética , Especies Reactivas de Oxígeno
5.
Opt Express ; 32(9): 15166-15176, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859175

RESUMEN

The refractive index (RI) measurment of the liquid often changes with the sensor's temperature. Accurate RI measurements require simultaneous measurements of the liquid temperature to calibrate the RI measurement. This study proposed what we believe to be a novel dual D-shaped plastic optical fiber sensor capable of simultaneously measuring both RI and temperature. A fluorescent material made of rhodamine B (RhB) is embedded in one of the D-shaped structures of the dual D-shaped fiber, which can be excited by a green laser to produce orange fluorescence. The fluorescence and the input laser of the fiber are superimposed at the output end of the fiber to form a specklegram containing information of two wavelengths. It was found through experiments that the effects of temperature and RI change on the red and green channels of the specklegrams are different, and the neural network can learn this feature to complete the measurement of both RI and temperature parameters. For RI sensing, the maximum error between the average predicted value and the true value of the test set is 0.0005. For temperature sensing, the maximum error between the average predicted value and the true value of the test set is 0.26°C. In addition, because the intensity change of the fluorescence varies linearly with RI and temperature, the sensor also has good stability.

6.
Biotechnol Bioeng ; 121(6): 2002-2012, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38555482

RESUMEN

The physiological role of Geobacter sulfurreducens extracellular cytochrome filaments is a matter of debate and the development of proposed electronic device applications of cytochrome filaments awaits methods for large-scale cytochrome nanowire production. Functional studies in G. sulfurreducens are stymied by the broad diversity of redox-active proteins on the outer cell surface and the redundancy and plasticity of extracellular electron transport routes. G. sulfurreducens is a poor chassis for producing cytochrome nanowires for electronics because of its slow, low-yield, anaerobic growth. Here we report that filaments of the G. sulfurreducens cytochrome OmcS can be heterologously expressed in Shewanella oneidensis. Multiple lines of evidence demonstrated that a strain of S. oneidensis, expressing the G. sulfurreducens OmcS gene on a plasmid, localized OmcS on the outer cell surface. Atomic force microscopy revealed filaments with the unique morphology of OmcS filaments emanating from cells. Electron transfer to OmcS appeared to require a functional outer-membrane porin-cytochrome conduit. The results suggest that S. oneidensis, which grows rapidly to high culture densities under aerobic conditions, may be suitable for the development of a chassis for producing cytochrome nanowires for electronics applications and may also be a good model microbe for elucidating cytochrome filament function in anaerobic extracellular electron transfer.


Asunto(s)
Citocromos , Geobacter , Shewanella , Shewanella/genética , Shewanella/metabolismo , Shewanella/enzimología , Geobacter/genética , Geobacter/metabolismo , Citocromos/metabolismo , Citocromos/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Transporte de Electrón , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Risk Anal ; 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212243

RESUMEN

In November 2022, the global human population reached 8 billion and is projected to reach 10 billion by 2060. Theories, models, and evidence indicate that global population growth (GPG) increases the likelihood of many adverse outcomes, such as biodiversity loss, climate change, mass migrations, wars, and resource shortages. A small body of research indicates that many individuals are concerned about the effects of GPG, and these concerns are strongly related to the willingness to engage in mitigative and preventative actions. However, scientific understanding of the factors that influence GPG risk perceptions remains limited. To help address this research gap, we conducted a study of the perceived risk of GPG among UK and US residents (N = 1029) shortly after the "8 billion milestone." Our results confirmed that GPG is perceived as a moderate-to-high risk and these perceptions have a strong positive relationship with the willingness to engage in and support risk management actions. Our participants believed that the worst effects of GPG were yet to come but would largely be geographically and socially remote. Despite their willingness to engage in risk management actions, our participants reported low self-efficacy and that governments (cf. individuals and communities) have the greatest capacity to influence GPG. Risk perceptions were strongly predicted by worldviews and were higher among our UK (cf. US) participants. We also found that the perceived benefits of GPG were low and found no evidence to suggest that risk perceptions were affected by exposure to media coverage of the 8 billion milestone.

8.
J Environ Manage ; 358: 120948, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38663081

RESUMEN

With the extensive industrialization and urbanization taking place in China during the recent decades, land use throughout the country has experienced profound changes influenced not only by the demand for population growth and living standard improvement but also by the constraints of series of land use policies. However, whether the conflict between the expansion of settlement land (SL) and the loss of cultivated land (CL) have been resolved at the national scale or transferred between the local regions remains unclear. Based on yearly ESA CCI land use and land cover products from 1992 to 2020, the long-term trends of quantity and spatial pattern of SL expansion and CL change in China from national and local views were investigated using trend statistic methods, and finally a comprehensive zoning framework was proposed to recognize the trade-off and synergies relationships between SL expansion and CL change. There are a continuous expansion of SL with global linear trends showing three breakpoints in 2000, 2005, and 2012, and a fluctuation decline of CL presented with four breakpoints in 1997, 2002, 2006, and 2013. Aggregation and dispersion tendencies with linear characteristics of SL expansion and CL change were found with breakpoints in 2001, 2008, 2012, and 2016 and breakpoints in 2001 and 2010, respectively. A spotty spatial pattern of SL was shown spatially coincident with urban agglomerations in China while the planar continuous characteristic was found for CL. Local counties were classified into five tradeoff and synergies zones (TSZs), where general synergies (G-S) and decoupling (D) of SL expansion and CL change were rare cases and the different change in quantity and trend of SL expansion and CL change in local counties was concealed by the national trend. A few scattered counties were belonging to G-S and D TSZs, while most of the counties in the central-east and western China were in General-Tradeoff (G-T) and Superior-Tradeoff (S-T) TSZs. Counties in south and north China with higher percentages of CL were more prevalent in Superior-Synergy (S-S) TSZ. Our findings explicated the complex relationships between SL expansion and CL change of China at the national scale and in local counties, which pointed out the differences of unified land use management activities across scales and could provide insights for future policy-making and management measures of land use to both ensure the national food security and promote regional sustainable development more synchronously.


Asunto(s)
Conservación de los Recursos Naturales , Urbanización , China , Agricultura , Humanos
9.
J Med Virol ; 95(8): e28998, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37548149

RESUMEN

Over 3 years, humans have experienced multiple rounds of global transmission of SARS-CoV-2 and its variants. In addition, the widely used vaccines against SARS-CoV-2 involve multiple strategies of development and inoculation. Thus, the acquired immunity established among humans is complicated, and there is a lack of understanding within a panoramic vision. Here, we provided the special characteristics of the cellular and humoral responses in 2-year convalescents after inactivated vaccines, in parallel to vaccinated COVID-19 naïve persons and unvaccinated controls. The decreasing trends of the IgG, IgA, and NAb, but not IgM of the convalescents were reversed by the vaccination. Both cellular and humoral immunity in convalescents after vaccination were higher than the vaccinated COVID-19 naïve persons. Notably, inoculation with inactivated vaccine fueled the NAb to BA.1, BA.2, BA.4, and BA.5 in 2-year convalescents, much higher than the NAb during 6 months and 1 year after symptoms onset. And no obvious T cell escaping to the S protein was observed in 2-year convalescents after inoculation. The study provides insight into the complicated features of human acquired immunity to SARS-CoV-2 and variants in the real world, indicating that promoting vaccine inoculation is essential for achieving herd immunity against emerging variants, especially in convalescents.


Asunto(s)
COVID-19 , Inmunidad Humoral , Humanos , COVID-19/prevención & control , Vacunas de Productos Inactivados , SARS-CoV-2 , Vacunas contra la COVID-19 , Anticuerpos Antivirales , Anticuerpos Neutralizantes
10.
Appl Opt ; 62(34): 8978-8986, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38108732

RESUMEN

Multiple-input multiple-output (MIMO) detectors have been a key technology in communication systems. In this paper, a new MIMO detector is designed by combining the adaptive learning rate (ALR) with the convolutional neural network (CNN) and successfully implementing it in a mode division multiplexing (MDM) optical transmission system. The results show that the training and test accuracy of the signal in the system we proposed reaches 100%. What is more, we used the ALR-CNN to compare the performance with conventional detection algorithms. The results confirm that our DLNN exceeds the conventional MIMO detectors in performance and is able to achieve the ideal QPSK BER level. The minimum difference in the SNR is about 9.5 dB at a BER of the 10-3 order.

11.
Appl Opt ; 62(18): 5023-5027, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37707280

RESUMEN

In this paper, the graphdiyne (GDY)-polymethyl methacrylate (PMMA) films are prepared by a spin-coating method. The PMMA films have the function of isolating GDY from air and protecting the GDY from mechanical damage. The nonlinear optical properties of GDY-PMMA films are probed experimentally. The nonlinear optical responses of GDY-PMMA films with a modulation depth of ∼4.94% and saturated magnetization of ∼0.3M W/c m 2 are proved. When the GDY-PMMA films are applied to an erbium-doped hybrid passively mode-locked fiber laser (saturable absorber), the bound-state solitons, which are also called soliton molecules, can be obtained. The soliton molecule has a time separation of 13.31 ps, and the spectral modulation period of 0.58 nm. Along with the pump power increase, the separation of bound-state pulses becomes larger. When the pump power is fixed, stable bound solitons can be observed without any degeneration for more than 4.5 h. It is demonstrated that GDY-PMMA films have excellent nonlinear optical performance in a near-infrared regime, which we believe can be a novel type of photonics instrument and has a number of properties that are potentially promising in the ultrafast properties of laser.

12.
Angew Chem Int Ed Engl ; 62(38): e202309005, 2023 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-37525962

RESUMEN

Electrobiocorrosion, the process in which microbes extract electrons from metallic iron (Fe0 ) through direct Fe0 -microbe electrical connections, is thought to contribute to the costly corrosion of iron-containing metals that impacts many industries. However, electrobiocorrosion mechanisms are poorly understood. We report here that electrically conductive pili (e-pili) and the conductive mineral magnetite play an important role in the electron transfer between Fe0 and Geobacter sulfurreducens, the first microbe in which electrobiocorrosion has been rigorously documented. Genetic modification to express poorly conductive pili substantially diminished corrosive pitting and rates of Fe0 -to-microbe electron flux. Magnetite reduced resistance to electron transfer, increasing corrosion currents and intensifying pitting. Studies with mutants suggested that the magnetite promoted electron transfer in a manner similar to the outer-surface c-type cytochrome OmcS. These findings, and the fact that magnetite is a common product of iron corrosion, suggest a potential positive feedback loop of magnetite produced during corrosion further accelerating electrobiocorrosion. The interactions of e-pili, cytochromes, and magnetite demonstrate mechanistic complexities of electrobiocorrosion, but also provide insights into detecting and possibly mitigating this economically damaging process.


Asunto(s)
Óxido Ferrosoférrico , Geobacter , Oxidación-Reducción , Electrones , Corrosión , Transporte de Electrón , Citocromos/metabolismo , Hierro , Geobacter/genética , Geobacter/metabolismo
13.
Clin Infect Dis ; 75(1): e1072-e1081, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34609506

RESUMEN

BACKGROUND: The longitudinal antigen-specific immunity in COVID-19 convalescents is crucial for long-term protection upon individual re-exposure to SARS-CoV-2, and even more pivotal for ultimately achieving population-level immunity. We conducted this cohort study to better understand the features of immune memory in individuals with different disease severities at 1 year post-disease onset. METHODS: We conducted a systematic antigen-specific immune evaluation in 101 COVID-19 convalescents, who had asymptomatic, mild, moderate, or severe disease, through 2 visits at months 6 and 12 after disease onset. The SARS-CoV-2-specific antibodies, comprising neutralizing antibody (NAb), immunoglobulin (Ig) G, and IgM, were assessed by mutually corroborated assays (ie, neutralization, enzyme-linked immunosorbent assay [ELISA], and microparticle chemiluminescence immunoassay [MCLIA]). Meanwhile, T-cell memory against SARS-CoV-2 spike, membrane, and nucleocapsid proteins was tested through enzyme-linked immunospot assay (ELISpot), intracellular cytokine staining, and tetramer staining-based flow cytometry, respectively. RESULTS: SARS-CoV-2-specific IgG antibodies, and NAb, can persist among >95% of COVID-19 convalescents from 6 to 12 months after disease onset. At least 19/71 (26%) of COVID-19 convalescents (double positive in ELISA and MCLIA) had detectable circulating IgM antibody against SARS-CoV-2 at 12 months post-disease onset. Notably, numbers of convalescents with positive SARS-CoV-2-specific T-cell responses (≥1 of the SARS-CoV-2 antigen S1, S2, M, and N proteins) were 71/76 (93%) and 67/73 (92%) at 6 and 12 months, respectively. Furthermore, both antibody and T-cell memory levels in the convalescents were positively associated with disease severity. CONCLUSIONS: SARS-CoV-2-specific cellular and humoral immunities are durable at least until 1 year after disease onset.


Asunto(s)
COVID-19 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Estudios de Cohortes , Humanos , Inmunidad Humoral , Inmunoglobulina G , SARS-CoV-2
14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 51(5): 563-572, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36581582

RESUMEN

OBJECTIVE: To investigate the effect and mechanism of Pinus massoniana needle extracts (PNE) on oxidative stress injury in cerebral ischemia reperfusion rats. METHODS: The SD male rats were randomly divided into sham group, model control group, Edaravone (3 mg/kg) group, PNE low-dose (200 mg/kg), medium-dose (400 mg/kg) and high-dose (800 mg/kg) groups. PNE was administered by gavage for 7 d before modeling and 6 h after modeling in PNE treatment groups; Edaravone was given by intraperitoneal injection 7 d before modeling and 6 h after reperfusion. The rat model of cerebral ischemia reperfusion injury was established by middle cerebral artery occlusion method. After 24 h of reperfusion, the neurological deficit score, brain water content and cerebral infarction volume of rats were measured. The pathological changes of cerebral cortex and hippocampus were observed by HE staining, and the number of normal nerve cells was counted. The apoptosis rate of neurons in cerebral cortex was detected by TUNEL method. The content of nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) activity in ischemic brain tissue were detected. The protein expression of c-Jun N-terminal kinase (JNK) 3, phosphorylated JNK3 (p-JNK3), B-cell lymphoma protein(Bcl) -2, Bcl-2 associated X (Bax), cytochrome C and caspase-3 in cerebral cortex were detected by Western blotting method. RESULTS: Compared with the model control group, the behavioral score, brain water content and cerebral infarction volume in PNE groups were significantly reduced (all P<0.05), the pathological damage of cerebral cortex and hippocampal CA1 area was significantly alleviated, and the number of normal nerve cells in ischemic cortex and hippocampal CA1 area was increased (all P<0.05). The medium-dose PNE group had the best effect. Compared with the model control group, the apoptosis rate of cortical neurons, the content of NO and MDA in cerebral cortex, the ratio of p-JNK3/JNK3, the expression level of cytochrome C and caspase-3 protein in PNE medium-dose group were significantly reduced , and the activity of SOD, the Bcl-2/Bax ratio were significantly improved (all P<0.05). CONCLUSION: PNE ameliorates brain injury after cerebral ischemia reperfusion in rats, which may be related to scavenging NO and MDA, inhibiting oxidative stress-mediated JNK3/caspase-3 signsal transduction to inhibit neuronal apoptosis.


Asunto(s)
Isquemia Encefálica , Estrés Oxidativo , Extractos Vegetales , Daño por Reperfusión , Animales , Masculino , Ratas , Apoptosis , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/farmacología , Proteína X Asociada a bcl-2/uso terapéutico , Isquemia Encefálica/tratamiento farmacológico , Caspasa 3/metabolismo , Caspasa 3/farmacología , Citocromos c/metabolismo , Citocromos c/farmacología , Citocromos c/uso terapéutico , Edaravona/farmacología , Edaravona/uso terapéutico , Infarto de la Arteria Cerebral Media , Ratas Sprague-Dawley , Reperfusión , Daño por Reperfusión/prevención & control , Daño por Reperfusión/tratamiento farmacológico , Transducción de Señal , Superóxido Dismutasa , Extractos Vegetales/farmacología , Pinus/química
15.
Neurochem Res ; 46(7): 1869-1880, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34031841

RESUMEN

Piceatannol is a natural plant-derived compound with protective effects against cardiovascular diseases. However, its effect on cerebral ischaemia-reperfusion injury (CIRI) induced by oxidative stress remains unclear. This study aimed to investigate piceatannol's antioxidation in CIRI. An in vitro oxygen-glucose deprivation followed by reoxygenation model was used and cell viability was measured. A middle cerebral artery occlusion followed by reperfusion model was used in vivo. Neurological function, encephalisation quotient, oedema, and volume of the cerebral infarction were then evaluated. The effects of piceatannol on histopathological findings, as well as the ultrastructure of the cortex, were analysed. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and lactate dehydrogenase (LDH) and the malondialdehyde (MDA) content was measured both in vitro and in vivo. Finally, the expression of nuclear factor erythroid-2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1), and nicotinamide adenine dinucleotide phosphate quinone oxidoreductase 1 (NQO1) in cerebral tissue was detected using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting. Our results demonstrated that cell viability in the piceatannol groups was increased. The SOD, GSH-Px activities were increased as LDH activity and MDA content decreased in the piceatannol groups both in vitro and in vivo, reflecting a decrease in oxidative stress. The neurological severity score and infarction volume in the piceatannol groups at doses of 10 and 20 mg/kg were lower than those of the model group. Furthermore, the damage seen on histopathological examination was partially attenuated by piceatannol. RT-qPCR and western blot analysis indicated that the expression of Nrf2, HO-1, and NQO1 were significantly increased by piceatannol. The results of the study demonstrate that piceatannol exerts a protective effect against CIRI.


Asunto(s)
Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Estilbenos/uso terapéutico , Animales , Encéfalo/patología , Hipoxia de la Célula/fisiología , Supervivencia Celular/efectos de los fármacos , Glucosa/deficiencia , Hemo-Oxigenasa 1/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Masculino , Proteínas de la Membrana/metabolismo , Ratones Endogámicos ICR , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
16.
Plant Dis ; 105(7): 1926-1935, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33289407

RESUMEN

The biocontrol efficacy of Bacillus amyloliquefaciens FS6 against seedling diseases and gray mold of ginseng (Panax ginseng), as well as application techniques, were evaluated in a series of field trials. FS6 fermentation broth showed a strong antagonistic effect against the ginseng fungal pathogens, and the inhibition rates on mycelial growth and spore germination were 84 to 88% and 71 to 72%, respectively. Field evaluation showed that combination of seed and soil treatments exhibited better protection than that of individual treatment alone. FS6 wettable powder soil treatment in combination with thiamethoxam plus metalaxyl-M plus fludioxonil for seed coating performed the best, with >83% overall control efficacy for seedling diseases. FS6 had a long-acting effect of >78% control efficacy on ginseng gray mold at 30 days after the last application, almost 2.5- and 2-fold better than that of B. amyloliquefaciens B7900 wettable powder and cyprodinil, respectively. In addition, FS6 reduced the diversity and relative abundance of fungi and affected the fungi and bacterial composition in the rhizosphere soil of ginseng. Therefore, FS6 can be used to effectively control seedling diseases and gray mold in ginseng.


Asunto(s)
Bacillus amyloliquefaciens , Agentes de Control Biológico , Panax , Enfermedades de las Plantas , Hongos , Enfermedades de las Plantas/prevención & control , Plantones
17.
BMC Immunol ; 21(1): 23, 2020 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-32349664

RESUMEN

BACKGROUND: CD8+CD28- T suppressor (Ts) cells play critical role in transplant tolerance. Our previous study has generated CD8+CD28- Ts cells in vitro which exert robust allospecific suppressive capacity in vitro. RESULTS: CD8+CD28- Ts cells were expanded by stimulating human CD8+ T cells with allogeneic antigen presenting cells in the presence of the common gamma chain cytokines IL-2, IL-7 and IL-15 in vitro, and were further verified in vitro through day 7 to 11 for their persistency of the allospecific suppressive capacity. When CD8+CD28- Ts cells were adoptively transferred into NOG mice, their capacity to inhibit CD4+ T cell proliferation in allospecific manner remained potent on 11 days after their injection. The mechanisms for expansion of CD8+CD28- Ts cells by the common gamma chain cytokines were investigated. These included promoting CD8+CD28- T cells proliferation, converting CD8+CD28+ T cells to CD8+CD28- T cells and decreasing CD8+CD28- T cell death. Furthermore, the expanded CD8+CD28- Ts cells showed upregulation of the co-inhibitory molecule Tim-3 and down-regulation of the cytotoxic molecule granzyme B. CONCLUSIONS: In summary, these results demonstrated that the in vitro-expanded human CD8+CD28- T cells retained potent allospecific suppressive capacity in vivo and depicted multiple mechanisms for the expansion of Ts cells, which might promote further bench to clinic research.


Asunto(s)
Antígenos CD28/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/inmunología , Animales , Células Presentadoras de Antígenos/inmunología , Muerte Celular/inmunología , Proliferación Celular/fisiología , Regulación hacia Abajo/inmunología , Femenino , Granzimas/inmunología , Humanos , Ratones , Regulación hacia Arriba/inmunología
18.
BMC Cancer ; 20(1): 1198, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33287749

RESUMEN

BACKGROUND: Lung cancer is the most frequently diagnosed carcinoma and the leading cause of cancer-related mortality. Although molecular targeted therapy and immunotherapy have made great progress, the overall survival (OS) is still poor due to a lack of accurate and available prognostic biomarkers. Therefore, in this study we aimed to establish a multiple-gene panel predicting OS for lung adenocarcinoma. METHODS: We obtained the mRNA expression and clinical data of lung adenocarcinoma (LUAD) from TCGA database for further integrated bioinformatic analysis. Lasso regression and Cox regression were performed to establish a prognosis model based on a multi-gene panel. A nomogram based on this model was constructed. The receiver operating characteristic (ROC) curve and the Kaplan-Meier curve were used to assess the predicted capacity of the model. The prognosis value of the multi-gene panel was further validated in TCGA-LUAD patients with EGFR, KRAS and TP53 mutation and a dataset from GEO. Gene set enrichment analysis (GSEA) was performed to explore potential biological mechanisms of a novel prognostic gene signature. RESULTS: A four-gene panel (including DKK1, GNG7, LDHA, MELTF) was established for LUAD prognostic indicator. The ROC curve revealed good predicted performance in both test cohort (AUC = 0.740) and validation cohort (AUC = 0.752). Each patient was calculated a risk score according to the model based on the four-gene panel. The results showed that the risk score was an independent prognostic factor, and the high-risk group had a worse OS compared with the low-risk group. The nomogram based on this model showed good prediction performance. The four-gene panel was still good predictors for OS in LUAD patients with TP53 and KRAS mutations. GSEA revealed that the four genes may be significantly related to the metabolism of genetic material, especially the regulation of cell cycle pathway. CONCLUSION: Our study proposed a novel four-gene panel to predict the OS of LUAD, which may contribute to predicting prognosis accurately and making the clinical decisions of individual therapy for LUAD patients.


Asunto(s)
Adenocarcinoma del Pulmón/genética , Nomogramas , Adenocarcinoma del Pulmón/mortalidad , Biomarcadores de Tumor , Femenino , Humanos , Masculino , Factores de Riesgo , Análisis de Supervivencia
19.
J Environ Sci (China) ; 84: 29-41, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31284914

RESUMEN

It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices. However, they are still produced at some plants in the world due to various reasons. Furthermore, calcium arsenates can also naturally precipitate under some specific environments. However, the transformation process of poorly crystalline calcium arsenates (PCCA) and the stability of these samples under atmospheric CO2 are not yet well understood. This work investigated the transformation process of PCCA produced by using different neutralization reagents (CaO vs. NaOH) with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2. After aging at room temperature for a period of time, for samples neutralized with NaOH and precipitated at pH 10 and 12, release of arsenic back into the liquid phase occurred. In contrast, for the samples precipitated at pH 8, the aqueous concentration of arsenic was observed to decrease. XRD, Raman, and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior. Moreover, the application of lime may enhance the stability of the generated PCCA. However, no matter what neutralization reagent is used, the stability of the generated PCCA is still of concern.


Asunto(s)
Arseniatos/química , Arsénico/análisis , Compuestos de Calcio/química , Precipitación Química
20.
Biochem Biophys Res Commun ; 501(4): 838-845, 2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-29705695

RESUMEN

Glyphosate is the active ingredient in numerous herbicide formulations. The roles of glyphosate in embryo-toxicity and neurotoxicity have been reported in human and animal models. Recently, several studies have reported evidence linking neurodevelopmental disorders (NDDs) with gestational glyphosate exposure. However, the role of glyphosate in neuronal development is still not fully understood. Our previous study found that perinatal glyphosate exposure resulted in differential microRNA expression in the prefrontal cortex of mouse offspring. However, the mechanism of glyphosate-induced neurotoxicity in the developing brain is still not fully understood. Considering the pivotal role of Circular RNAs (circRNAs) in the regulation of gene expression, a circRNA microarray method was used in this study to investigate circRNA expression changes in the hippocampus of mice with perinatal glyphosate exposure. The circRNA microarrays revealed that 663 circRNAs were significantly altered in the perinatal glyphosate exposure group compared with the control group. Among them, 330 were significantly upregulated, and the other 333 were downregulated. Furthermore, the relative expression levels of mmu-circRNA-014015, mmu-circRNA-28128 and mmu-circRNA-29837 were verified using quantitative real-time polymerase chain reaction (qRT-PCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that stress-associated steroid metabolism pathways, such as aldosterone synthesis and secretion pathways, may be involved in the neurotoxicity of glyphosate. These results showed that circRNAs are aberrantly expressed in the hippocampus of mice with perinatal glyphosate exposure and play potential roles in glyphosate-induced neurotoxicity.


Asunto(s)
Perfilación de la Expresión Génica , Glicina/análogos & derivados , Hipocampo/metabolismo , Efectos Tardíos de la Exposición Prenatal/genética , ARN/genética , Animales , Biología Computacional , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Ontología de Genes , Redes Reguladoras de Genes/efectos de los fármacos , Glicina/toxicidad , Hipocampo/efectos de los fármacos , Ratones Endogámicos ICR , Análisis de Secuencia por Matrices de Oligonucleótidos , Embarazo , ARN/metabolismo , ARN Circular , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética , Glifosato
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