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1.
J Environ Manage ; 356: 120679, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531141

RESUMO

Introduction of alpine grasses to low altitude regions has long been a crucial strategy for enriching germplasm diversity, cultivating and acclimating high-quality species, enhancing ecosystem resilience and adaptability, as well as facilitating ecosystem restoration. However, there is an urgent need to investigate the impacts of planting Gramineae seeds on greenhouse gas (GHG) emissions, particularly during the critical stage of early plant growth. In this study, four species of grass seeds (Stipa breviflora, Poa pratensis, Achnatherum splendens, Elymus nutans) were collected from 19 high-altitude regions surrounding the Qinghai-Tibet Plateau and sown at low-altitude. Measurements of GHG emissions at early seedling growth in the mesocosm experiment using static chamber method showed a strong increase in the cumulative emissions of CO2 (5.71%-9.19%) and N2O (11.36%-13.64%) (p < 0.05), as well as an elevated CH4 uptake (2.75%-5.50%) in sites where the four grass species were introduced, compared to bare soil. Consequently, there was a substantial rise in global warming potential (13.87%-16.33%) (p < 0.05) at grass-introduced sites. Redundancy analysis showed that seed traits, plant biomass, and seedling emergence percentage were the main driving biotic factors of three GHGs fluxes. Our study unveils the potential risk of escalating GHG emissions induced by introducing high altitude grasses to low altitude bare soil, elucidating the mechanism through linking seed traits with seedling establishment and environmental feedback. Furthermore, this offers a new perspective for assessing the impact of grass introduction on ecological environment of introduced site.


Assuntos
Aquecimento Global , Gases de Efeito Estufa , Ecossistema , Plântula/química , Poaceae , Altitude , Solo , Metano/análise , Óxido Nitroso/análise , Dióxido de Carbono/análise
2.
J Agric Food Chem ; 72(13): 6988-6997, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506764

RESUMO

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv oryzae (Xoo) is extremely harmful to rice production. The traditional control approach is to use bactericides that target key bacterial growth factors, but the selection pressure on the pathogen makes resistant strains the dominant bacterial strains, leading to a decline in bactericidal efficacy. Type III secretion system (T3SS) is a conserved and critical virulence factor in most Gram-negative bacteria, and its expression or absence does not affect bacterial growth, rendering it an ideal target for creating drugs against Gram-negative pathogens. In this work, we synthesized a range of derivatives from cryptolepine and neocryptolepine. We found that compound Z-8 could inhibit the expression of Xoo T3SS-related genes without affecting the growth of bacteria. an in vivo bioassay showed that compound Z-8 could effectively reduce the hypersensitive response (HR) induced by Xoo in tobacco and reduce the pathogenicity of Xoo in rice. Furthermore, it exhibited synergy in control of bacterial leaf blight when combined with the quorum quenching bacterial F20.


Assuntos
Alcaloides , Alcaloides Indólicos , Oryza , Quinolinas , Xanthomonas , Oryza/genética , Sistemas de Secreção Tipo III/genética , Bactérias/metabolismo , Xanthomonas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37644749

RESUMO

BACKGROUND: Diabetic peripheral neuropathy causes significant pain to patients. Umbilical cord mesenchymal stem cells have been shown to be useful in the treatment of diabetes and its complications. The aim of this study was to investigate whether human umbilical cord mesenchymal stem cells treated with interferon-gamma can ameliorate nerve injury associated with diabetes better than human umbilical cord mesenchymal stem cells without interferon-gamma treatment. METHODS: Human umbilical cord mesenchymal stem cells were assessed for adipogenic differentiation, osteogenic differentiation, and proliferation ability. Vonfry and a hot disc pain tester were used to evaluate tactile sensation and thermal pain sensation in mice. Hematoxylin-eosin and TUNEL staining were performed to visualize sciatic nerve fiber lesions and Schwann cell apoptosis in diabetic mice. Western blotting was used to detect expression of the apoptosis-related proteins Bax, B-cell lymphoma-2, and caspase-3 in mouse sciatic nerve fibers and Schwann cells. Real-Time Quantitative PCR was used to detect mRNA levels of the C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10 in mouse sciatic nerve fibers and Schwann cells. Enzyme-linked immunosorbent assay was used to detect levels of the inflammatory cytokines, interleukin-1ß, interleukin-6, and tumor necrosis factor-α in serum and Schwann cells. RESULTS: The adipogenic differentiation capacity, osteogenic differentiation capacity, and proliferation ability of human umbilical cord mesenchymal stem cells were enhanced after interferon-gamma treatment. Real-Time Quantitative PCR revealed that interferon-gamma promoted expression of the adipogenic markers, PPAR-γ and CEBP-α, as well as of the osteogenic markers secreted phosphoprotein 1, bone gamma-carboxyglutamate protein, collagen type I alpha1 chain, and Runt-related transcription factor 2. The results of hematoxylin-eosin and TUNEL staining showed that pathological nerve fiber damage and Schwann cell apoptosis were reduced after the injection of interferon-gamma-treated human umbilical cord mesenchymal stem cells. Expression of the apoptosis-related proteins, caspase-3 and Bax, was significantly reduced, while expression of the anti-apoptotic protein B-cell lymphoma-2 was significantly increased. mRNA levels of the cell chemokines, C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10, were significantly reduced, and levels of the inflammatory cytokines, interleukin-1ß, interleukin-6, and tumor necrosis factor-α, were decreased. Tactile and thermal pain sensations were improved in diabetic mice. CONCLUSION: Interferon-gamma treatment of umbilical cord mesenchymal stem cells enhanced osteogenic differentiation, adipogenic differentiation, and proliferative potential. It can enhance the ability of human umbilical cord mesenchymal stem cells to alleviate damage to diabetic nerve fibers and Schwann cells, in addition to improving the neurological function of diabetic mice.

4.
Orthop Surg ; 15(9): 2260-2266, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37476856

RESUMO

OBJECTIVE: Pedicle screw implantation is the most common technique to achieve stability during spinal surgeries. Current methods for locating the entry point do not have a quantified criteria and highly rely on the surgeons' experience. Therefore, we aim to propose a quantified pedicle screw placement technique in the lumbar spine and to investigate its accuracy and safety in clinical practice. METHODS: We conducted a retrospective study involving 110 patients who received spinal surgery in our hospital from August 2018 to August 2021. All patients included had herniation of a single lumbar disc and were consistently treated with posterior discectomy, inter-body fusion, and transpedicular internal fixation. For 54 patients in the observation group, the pedicle screws were placed with our technique, which is located at 4 mm below the superior edge of the transverse process in line with the lateral margin of the superior articular process. For 56 patients in the control group, pedicle screws were placed according to the traditional crista lambdoidalis method. Comparisons were made in terms of the operation time, blood loss, time for exposure, the accuracy of placement, and postoperative complications. Furthermore, we applied our method to 64 patients with indistinguishable crista lambdoidalis and evaluated the accuracy of screw placement and clinical outcomes according to the visual analogue scale (VAS) and the Japanese Orthopaedic Association (JOA) score. RESULTS: There was no significant difference in intraoperative bleeding, accuracy of placement, and postoperative complications between our technique and the traditional crista lambdoidalis method (P > 0.05). However, the exposure time before screw placement (12.8 ± 0.3 vs. 17.4 ± 0.3, P = 0.001) and the total surgery time (97.2 ± 1.9 vs 102.3 ± 0.9, P = 0.020) were significantly shortened with our method. Additionally, in cases with indistinguishable crista lambdoidalis, our technique showed satisfying accuracy, with 97.6% screws placed in appropriate trajectory on the first attempt and all screws eventually positioned in the safe zone according to the Gertzbein-Robbins grading. All patients experienced steady improvement after surgery. CONCLUSION: Placing pedicle screws at 4 mm below the superior edge of the transverse process in line with the lateral margin of the superior articular process is a viable pedicle screw placement method. With this method, we observed a higher success rate and shorter operation time. In addition, this method can be applied in cases with indistinguishable crista lambdoidalis, and have satisfied success rate and clinical outcome.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Parafusos Pediculares/efeitos adversos , Estudos Retrospectivos , Fusão Vertebral/métodos , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/etiologia
5.
Pest Manag Sci ; 79(8): 2748-2761, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36914877

RESUMO

BACKGROUND: The unreasonable use of chemical fungicides causes common adverse consequences that not only affect the environment, but also cause resistance and resurgence problems of plant pathogens, which are extremely harmful to human health, the economy, and the environment. Based on the rich biological activities of boron-based compounds, 82 phenylboronic acid derivatives were selected and their antifungal activities against six agricultural plant pathogens were determined. Combined with transcriptomics tools, the mechanism of action of compound A49 (2-chloro-5-trifluoromethoxybenzeneboronic acid) against Botrytis cinerea Pers (B. cinerea) was studied. RESULTS: The EC50 values of compounds A24, A25, A30, A31, A36, A41, A49 and B23 against all six fungi were under 10 µg/mL. Compound A49 displayed significant activity against B. cinerea (EC50 = 0.39 µg/mL), which was better than that of commercial fungicide boscalid (EC50 = 0.55 µg/mL). A49 not only inhibited the germination of B. cinerea spores, but also caused abnormal cell morphology, loss of cell membrane integrity, enhanced cell membrane permeability, and accumulation of intracellular reactive oxygen species. Further findings showed that A49 reduced cellular antioxidant activity, and peroxidase and catalase activities. Transcriptomic results indicated that A49 could degrade intracellular redox processes and alter the metabolism of some amino acids. Meanwhile, A49 showed obvious activity in vivo and low cytotoxicity to mammal cells. CONCLUSION: The boron-containing small molecule compounds had high efficiency and broad-spectrum antifungal activities against six plant pathogens, and are expected to be candidate compounds for a new class of antifungal drugs. © 2023 Society of Chemical Industry.


Assuntos
Antifúngicos , Fungicidas Industriais , Humanos , Antifúngicos/farmacologia , Antifúngicos/química , Boro , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Botrytis , Relação Estrutura-Atividade
7.
Environ Sci Pollut Res Int ; 30(7): 18764-18776, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36219285

RESUMO

Welding is widely used to make assembly of structural components and it will trigger serious environmental pollution, especially waste gas, i.e., carbon dioxide (CO2), ozone (O3), nitrogen oxide (NOx), and particulate matter (PM). It is hard to accurately measure gas pollutants because of their fluidity and diffusivity. However, the pollutants could be evaluated by exploring its generation procedure, i.e., how these pollutants are produced and how to quantify these pollutants. In this paper, an arc profile-based approach to evaluate the emissions of gas pollutants in welding was proposed. The emission of gas pollutants in welding can be calculated according to the chemical reaction and corresponding reaction condition, i.e., the intensity of discharge that determines the coverage volume of the welding arc. To obtain the coverage volume, the welding arc was observed using a high-speed camera and the arc edge was extracted and reconstructed by a binarization processing based method. A welding experiment was performed for recording the arc shape and measuring the emission of gas pollutants. Results show that the measured concentrations of NOx and O3 are 70% and 79% of the calculated emissions of gas pollutants, respectively. It demonstrates the proposed method is credible and feasible, which can help quantitatively analyze the emission of gas pollutants. Meanwhile, the influence of welding time, welding current, and arc length on the emission of gas pollutants was investigated for lowering emission of gas pollution in welding, in order to support the development of sustainable manufacturing processes.


Assuntos
Poluentes Ocupacionais do Ar , Poluentes Ambientais , Exposição Ocupacional , Soldagem , Poluentes Ocupacionais do Ar/análise , Soldagem/métodos , Exposição Ocupacional/análise , Material Particulado/análise , Óxido Nítrico
8.
Opt Lett ; 47(10): 2606-2609, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561412

RESUMO

Due to the many available cavity configurations, a generalized approach for identifying the optimal operating state of a Figure-9 mode-locked laser has proved a challenge. In this Letter, we probe the output pulsation states of an exemplar Figure-9 laser by meticulously scanning its parameter space. Regions corresponding to mode-locked operations are identified periodically in the map of the output states. We correlate these regions to a set of band-like cavity transmission functions that fundamentally allow ultra-short pulse formation. Interestingly, a clear correlation between the mode-locking pattern and the cavity configuration is observed. For example, with the decrease of the fiber loop symmetry in the cavity, half of the solutions in the mode-locking pattern are found to transit to forbidden states. Numerical calculations based on the Jones matrix are used to explain the experimental observations. In addition, the dynamic change of the map of output states is illustrated by using a setup with an automatic algorithm. Our results provide a visually-rich yet simple way for evaluating and optimizing a Figure-9 laser.

9.
J Agric Food Chem ; 70(5): 1467-1476, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35080386

RESUMO

A series of steroidal piperidone derivatives were synthesized, and their agricultural activities were evaluated against Myzus persicae, Aphis citricola, Brevicoryne brassicae Linn., and Bemisia tabaci (Gennadius). Most of the tested compounds exhibited potent insecticidal activity against these four pests. Compound I-9 displayed the highest activity against M. persicae, A. citricola, and Brevicoryne brassicae, with LC50 values of 11.3, 10.4, and 8.68 µg/mL, respectively. The mode of action test indicated that these derivatives had superior contact and systemic insecticidal activity against M. persicae. In addition, we initially explored whether the foregut and midgut might be the action sites of the target derivatives against M. persicae. Furthermore, a field trial showed that the control of compound I-9 was similar to that of acetamiprid against M. persicae, at a dose of 50 µg/mL; the control rates were 97.8 and 99.2% after 14 and 21 days, respectively. The structure-activity relationship of these analogues provided some important insights for the discovery and development of new insecticides to solve the current pesticide resistance crisis.


Assuntos
Afídeos , Inseticidas , Piperidonas , Animais , Inseticidas/farmacologia , Relação Estrutura-Atividade
10.
Opt Lett ; 47(21): 5668-5671, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219299

RESUMO

Hysteresis is a common phenomenon in passively mode-locked lasers and refers to the effect where the thresholds marking transitions between different pulsation states are not the same for an increasing or decreasing pump power. Despite wide presence in experimental observations, the general dynamics of hysteresis remains elusive, largely due to the challenge to acquire the full hysteresis dynamics of a given mode-locked laser. In this Letter, we overcome this technical bottleneck by fully characterizing an exemplar figure-9 fiber laser cavity, which exhibits well-defined mode-locking patterns in its parameter space or "primitive cell." We varied the net cavity dispersion and observed the salient change of hysteresis characteristics. Specifically, transiting from an anomalous to a normal cavity dispersion is found to consistently increase the likelihood of the single-pulse mode-locking regime. To the best of our knowledge, this is the first time that a laser's hysteresis dynamic is fully probed and related to fundamental cavity parameters.

11.
Opt Express ; 29(23): 37695-37702, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808836

RESUMO

GHz pulsed thulium-doped fiber laser with stabilized repetition rate can enable a wide range of applications. By employing regenerative mode-locking and cavity stabilization technique, we have for the first time demonstrated a 10 GHz polarization-maintaining thulium-doped fiber laser, which has a long-term repetition-rate stabilization and picosecond timing-jitter. In our experiment, a RF circuitry is designed to extract the 10 GHz longitudinal clock signal so that stable regenerative mode-locking is achieved. A piezo actuator-based phase-lock-loop is used to lock the regeneratively mode-locked pulses to a local reference synthesizer. The regeneratively mode-locked pulses with picosecond pulse width exhibit a high super-mode suppression ratio of 60 dB. In addition, the repetition rate of the laser shows good long-term stability with a variation of 8 Hz in 8 hours, corresponding to a cavity free spectral range fluctuation of less than 16 mHz. Meanwhile, the Allan deviation of the stabilized 10 GHz regeneratively mode-locked pulses is measured to be as low as 2 × 10-12 over 1000 s average time, which is only limited by the stability of the reference synthesizer. Such an ultra-stable 10 GHz pulsed thulium fiber laser may find potential application in 2 µm optical communication, material processing and spectroscopy.

12.
Steroids ; 176: 108931, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34655595

RESUMO

A series of thirty-six steroidal pyrazole amides, divided into two categories based on their main skeletons were designed and synthesized via a five-step synthetic route. The final product is obtained through Pinnick oxidation of pyrazole aldehydes to yield the corresponding acids, which then underwent amidation to afford the target products efficiently under mild reaction conditions. Structures of the desired compounds were confirmed by 1H NMR, 13C NMR, high resolution mass spectrometry; X-ray structural characterization of compound 16n was also obtained. The synthesized compounds were screened for their antiproliferative activity against four cancer cell lines (Pc-3 A549, Hela, HepG2) using the SRB method. Amides 10n, 16n, and 16p-16t exhibited moderate to high cytotoxic activities with IC50 values ranging from 2.05 to 8.73 µM. Of note, the hydrochloride derivative 16p displayed the highest activity towards PC-3 cells with IC50 values of 2.05 µM. Analysis of structure-activity relationships indicated that the presence of the diamine moiety and the aqueous solubility of the derivatives were vital factors for antiproliferative potency. Furthermore, molecule 16p induced PC-3 cells apoptosis and arrested cell cycle at G1 phase in a dose-dependent manner.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Pirazóis/farmacologia , Esteroides/farmacologia , Amidas/síntese química , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Pirazóis/síntese química , Pirazóis/química , Estereoisomerismo , Esteroides/síntese química , Esteroides/química , Relação Estrutura-Atividade
13.
J Agric Food Chem ; 69(39): 11572-11581, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34554742

RESUMO

A series of novel steroidal derivatives with a substituted 1,3,4-oxadiazole structure was designed and synthesized, and the target compounds were evaluated for their insecticidal activity against five aphid species. Most of the tested compounds exhibited potent insecticidal activity against Eriosoma lanigerum (Hausmann), Myzus persicae, and Aphis citricola. Compounds 20g and 24g displayed the highest activity against E. lanigerum, showing LC50 values of 27.6 and 30.4 µg/mL, respectively. Ultrastructural changes in the midgut cells of E. lanigerum were detected by transmission electron microscopy, indicating that these steroidal oxazole derivatives might exert their insecticidal activity by destroying the mitochondria and nuclear membranes in insect midgut cells. Furthermore, a field trial showed that compound 20g exhibited effects similar to those of the positive controls chlorpyrifos and thiamethoxam against E. lanigerum, reaching a control rate of 89.5% at a dose of 200 µg/mL after 21 days. We also investigated the hydrolysis and metabolism of the target compounds in E. lanigerum by assaying the activities of three insecticide-detoxifying enzymes. Compound 20g at 50 µg/mL exhibited inhibitory action on carboxylesterase similar to the known inhibitor triphenyl phosphate. The above results demonstrate the potential of these steroidal oxazole derivatives to be developed as novel pesticides.


Assuntos
Afídeos , Inseticidas , Praguicidas , Animais , Inseticidas/farmacologia , Oxidiazóis/farmacologia
14.
Front Oncol ; 11: 632976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816273

RESUMO

MicroRNAs (miRNAs) participated in the regulation of tumorigenesis, progression, metastasis, recurrence and chemo-resistance of cancers. However, the potential function of miRNAs in cancer stem cells (CSCs) or tumor-initiating cells (T-ICs) was not clearly elucidated. In the present study, we found that miR-186 expression was reduced in liver CSCs. Functional studies showed that miR-186 knockdown facilitated liver CSCs self-renewal and tumorigenesis. Conversely, forced miR-186 expression suppressed liver CSCs self-renewal and tumorigenesis. Mechanically, miR-186 downregulated PTPN11 via binding to its 3'-UTR in liver CSCs. The correlation of miR-186 and PTPN11 was confirmed in Hepatocellular carcinoma (HCC) patients' tissues. Further study showed that interference of PTPN11 can abolished the discrepancy between miR-186 mimic and control HCC cells in self-renewal and the proportion of CSCs. Additionally, we found that miR-186 overexpression HCC cells were more sensitive to cisplatin treatment. Clinical cohort analysis showed that HCC patients with high miR-186 were benefited more from transcatheter arterial chemoembolization (TACE) treatment. In conclusion, our study demonstrates a new regulation mechanism of liver CSCs, a new target for HCC, and a biomarker for postoperative TACE.

15.
ACS Appl Mater Interfaces ; 13(16): 18604-18618, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33856200

RESUMO

Microfluctuations in a pH gradient create a harsh microenvironment in tumors, leaving behind the most aggressive, invasive, and drug-resistant tumor cells. Directly visualizing the spatiotemporal distribution of pH variations and accurately quantifying the dynamic acid-base changes during cancer treatment are critical to estimate prognosis and to evaluate therapeutic efficacy. However, the quantification of subtle pH variations dynamically and noninvasively remains challenging. The purpose of this study is to determine and visualize dynamic acid-base changes in solid tumors during anti-acid treatments by magnetic resonance imaging (MRI) using pH-sensitive nanoparticles. We report the development of pH-sensitive nanoparticles, MnO2@BSA, that rapidly and strongly amplify the MR contrast signal in response to the extracellular acidic environment of solid tumors. The spatiotemporal distribution and dynamic fluctuations of pH heterogeneity in NCI-H460 lung tumors were observed with MnO2@BSA at different time points after an anti-acid treatment with esomeprazole, which directly interferes with the acidic microenvironment of the tumor. Imaging results were validated using a pH microsensor. MRI of pH-sensitive MnO2@BSA nanoparticles provided direct readouts of the kinetics of pH gradient fluctuations during esomeprazole treatment. A significant MR signal reduction was observed at the 48 h time point after treatment. The manipulated extracellular pH changes detected noninvasively by MRI coincided with the extracellular pH fluctuations measured with a pH microsensor (pH 6.12-6.63). Immunofluorescence and Western blot analyses confirmed the expression of V-ATPase in NCI-H460 lung cancer cells, which could be inhibited by esomeprazole, as detected by ELISA assay. Overall, these results demonstrate that MnO2@BSA MRI has great potential as a noninvasive tool to accurately monitor pH fluctuations, thereby paving the way for the dynamic detection of acidic microenvironments in vivo without the need for pH microsensors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Imageamento por Ressonância Magnética , Compostos de Manganês/química , Nanopartículas/química , Óxidos/química , Soroalbumina Bovina/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microambiente Tumoral/efeitos dos fármacos
16.
Folia Neuropathol ; 59(4): 335-349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35114774

RESUMO

Remote ischemic perconditioning (RIPerC) could improve neuronal damage and inhibit inflammation and apoptosis. We conducted an in-depth exploration of the protective mechanism of RIPerC in cerebral ischaemia injury. In this study, a middle cerebral artery occlusion (MCAO) mouse model was built. According to whether to undergo RIPerC treatment and the duration of cerebral infarction, mice were divided into 5 groups: Sham group, MCAO 3.0 h group, MCAO 4.5 h group, MCAO 3.0 h + RIPerC group, and MCAO 4.5 h + RIPerC group. Overexpressed or silenced miR-153-5p was transfected into the cells to analyse the effects of oxygen-glucose deprivation (OGD) treatment on Neuro-2a cell viability, apoptosis, and related gene expressions by performing quantitative real-time polymerase chain reaction (qRT-PCR), MTT assay, flow cytometry, and Western blot. Bioinformatics analysis, qRT-PCR, dual-luciferase experiment, and RNA immunoprecipitation (RIP) were used to screen and verify the miRNA and downstream mRNA-targeted Toll-like receptor 4 (TLR4). The rescue test further verified the effects of the above target genes and miR-153-5p on the apoptosis of OGD-injured cells, apoptosis-related proteins, and the p65/IkBa pathway. The plasma levels of miR-153-5p in 68 patients with ischaemic stroke were detected within 6 hours of onset, and the patients were followed up for 3 months. We found that, in in vivo studies, RIPerC treatment inhibits cerebral infarction volume and neurological damage, and promotes the expression of miR-153-5p in the MCAO animal model. The expression of miR-153-5p in OGD cells was inhibited, and its upregulation protected Neuro-2a cells. TLR4 was predicted to be the target gene of miR-153-5p and could offset the effect of miR-153-5p mimic on OGD cell protection after up-regulating TLR4. TLR4 overexpression promoted the activation of OGD on the p65/IkBa pathway. Compared with the high plasma miR-153-5p group, the 3-month overall survival rate of patients with ischaemic stroke in the low plasma miR-153-5p group was significantly lower (c2 = 5.095, p = 0.024). In conclusion, RIPerC intervention inhibits the damage caused by cerebral ischaemia partially through the miR-153-5p/TLR4/p65/IkBa signalling pathway.


Assuntos
Isquemia Encefálica , Precondicionamento Isquêmico , AVC Isquêmico , Transdução de Sinais , Animais , Apoptose , Isquemia Encefálica/terapia , Humanos , Infarto da Artéria Cerebral Média , AVC Isquêmico/terapia , Camundongos , MicroRNAs/genética , Inibidor de NF-kappaB alfa , Receptor 4 Toll-Like/genética , Fator de Transcrição RelA
17.
Signal Transduct Target Ther ; 5(1): 296, 2020 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-33361765

RESUMO

Hepatocyte nuclear factor 3γ (HNF3γ) is a hepatocyte nuclear factor, but its role and clinical significance in hepatocellular carcinoma (HCC) remain unclear. Herein, we report that HNF3γ expression is downregulated in patient HCC and inversely correlated with HCC malignancy and patient survival. Moreover, our data suggested that the HNF3γ reduction in HCC could be mediated by METTL14-dependent m6A methylation of HNF3γ mRNA. HNF3γ expression was increased during hepatic differentiation and decreased in dedifferentiated HCC cells. Interestingly, HNF3γ delivery promoted differentiation of not only HCC cells but also liver CSCs, which led to suppression of HCC growth. Mechanistic analysis suggested an HNF3γ-centered regulatory network that includes essential liver differentiation-associated transcription factors and functional molecules, which could synergistically facilitate HCC cell differentiation. More importantly, enforced HNF3γ expression sensitized HCC cells to sorafenib-induced growth inhibition and cell apoptosis through transactivation of OATP1B1 and OATP1B3 expression, which are major membrane transporters for sorafenib uptake. Clinical investigation showed that patient-derived HCC xenografts with high HNF3γ expression exhibited a sorafenib response and patients with high HCC HNF3γ levels benefited from sorafenib therapy. Together, these results suggest that HNF3γ plays an essential role in HCC differentiation and may serve as a therapeutic target and predictor of sorafenib benefit in patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Desdiferenciação Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fator 3-gama Nuclear de Hepatócito/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Sorafenibe/farmacologia , Animais , Anticorpos Heterófilos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Proteínas de Neoplasias/genética , Transplante de Neoplasias , RNA Neoplásico/genética
18.
Zhongguo Zhong Yao Za Zhi ; 45(12): 2772-2783, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32627450

RESUMO

Periplocae Cortex is a traditional Chinese medicine in China, which is mainly produced in northeast China, north China, northwest China, southwest China. In recent years, the increasing in-depth research resulted in the discovery of anti-tumor and cardiac pharmacological activities of Periplocae Cortex, which has broad application prospects. On the basis of summarizing chemical components and pharmacological effects, combined with the theoretical system of Q-marker, the quality control components of Periplocae Cortex were predicted from the aspects of the correlation between chemical composition and traditional medicinal properties, traditional efficacy, and new clinical use, plasma composition, measurable composition, storage time by analyzing literature. Among the components, periplocoside, periplocin, periplogenin, 4-methoxy salicylaldehyde showed significant activity, which provides a scientific basis for quality evaluation of Periplocae Cortex.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicina Tradicional Chinesa , Biomarcadores , China , Controle de Qualidade
19.
Gut ; 68(10): 1858-1871, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31118247

RESUMO

BACKGROUND AND AIMS: The unique expression pattern makes oncofetal proteins ideal diagnostic biomarkers and therapeutic targets in cancer. However, few oncofetal proteins have been identified and entered clinical practice. METHODS: Fetal liver, adult liver and hepatocellular carcinoma (HCC) tissues were employed to assess the expression of hepatic leukaemia factor (HLF). The impact of HLF on HCC onset and progression was investigated both in vivo and in vitro. The association between HLF and patient prognosis was determined in patient cohorts. The correlation between HLF expression and sorafenib benefits in HCC was further evaluated in patient cohorts and patient-derived xenografts (PDXs). RESULTS: HLF is a novel oncofetal protein which is reactivated in HCC by SOX2 and OCT4. Functional studies revealed that HLF transactivates c-Jun to promote tumour initiating cell (TIC) generation and enhances TIC-like properties of hepatoma cells, thus driving HCC initiation and progression. Consistently, our clinical investigations elucidated the association between HLF and patient prognosis and unravelled the close correlation between HLF levels and c-Jun expression in patient HCCs. Importantly, HLF/c-Jun axis determines the responses of hepatoma cells to sorafenib treatment, and interference of HLF abrogated c-Jun activation and enhanced sorafenib response. Analysis of patient cohorts and PDXs further suggests that HLF/c-Jun axis might serve as a biomarker for sorafenib benefits in HCC patients. CONCLUSIONS: Our findings uncovered HLF as a novel oncofetal protein and revealed the crucial role of the HLF/c-Jun axis in HCC development and sorafenib response, rendering HLF as an optimal target for the prevention and intervention of HCC.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Carcinoma Hepatocelular/genética , Resistencia a Medicamentos Antineoplásicos , Genes jun/genética , Neoplasias Hepáticas/genética , Sorafenibe/farmacologia , Adulto , Antineoplásicos/farmacologia , Apoptose , Fatores de Transcrição de Zíper de Leucina Básica/biossíntese , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Humanos , Imunoprecipitação , Zíper de Leucina , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Prognóstico
20.
Am J Chin Med ; 42(4): 921-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25004883

RESUMO

Humulus scandens, rich in flavonoids, is a traditional Chinese medicine. It is widely used in China to treat tuberculosis, dysentery and chronic colitis. In this study, the major active faction of Humulus scandens (H.S) was prepared. Then, its immunosuppressive effects and underlying mechanisms on T cell activation were investigated in vitro and in vivo. Results showed that H.S significantly inhibited the proliferation of splenocytes induced by concanavalin A, lipopolysaccharides, and mixed-lymphocyte reaction in vitro. Additionally, H.S could dramatically suppress the proliferation and interferon-γ (IFN-γ) production from T cells stimulated by anti-CD3 and anti-CD28. Flow cytometric results confirmed that H.S could suppress the differentiation of IFN-γ-producing type 1 helper T cells (Th1). Furthermore, using ovalbumin immunization-induced T cell reaction and CD4(+) T-cell-mediated delayed type hypersensitivity reaction, H.S the immunosuppressive effects of H.S was also demonstrated in vivo. Western blot results showed that H.S could impede the activation of both Erk1/2 and P38 in primary T cells triggered by anti-CD3/28. Collectively, the active fraction of H.S showed promising immunosuppressive activities both in vitro and in vivo.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Humulus , Imunossupressores , Ativação Linfocitária/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Concanavalina A/imunologia , Feminino , Hipersensibilidade Tardia/tratamento farmacológico , Hipersensibilidade Tardia/imunologia , Interferon gama/metabolismo , Lipopolissacarídeos/imunologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia , Extratos Vegetais/uso terapêutico , Células Th1/imunologia
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