Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
1.
Plant Cell ; 36(6): 2117-2139, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38345423

RESUMO

Plants have evolved complex mechanisms to adapt to harsh environmental conditions. Rice (Oryza sativa) is a staple food crop that is sensitive to low temperatures. However, its cold stress responses remain poorly understood, thus limiting possibilities for crop engineering to achieve greater cold tolerance. In this study, we constructed a rice pan-transcriptome and characterized its transcriptional regulatory landscape in response to cold stress. We performed Iso-Seq and RNA-Seq of 11 rice cultivars subjected to a time-course cold treatment. Our analyses revealed that alternative splicing-regulated gene expression plays a significant role in the cold stress response. Moreover, we identified CATALASE C (OsCATC) and Os03g0701200 as candidate genes for engineering enhanced cold tolerance. Importantly, we uncovered central roles for the 2 serine-arginine-rich proteins OsRS33 and OsRS2Z38 in cold tolerance. Our analysis of cold tolerance and resequencing data from a diverse collection of 165 rice cultivars suggested that OsRS2Z38 may be a key selection gene in japonica domestication for cold adaptation, associated with the adaptive evolution of rice. This study systematically investigated the distribution, dynamic changes, and regulatory mechanisms of alternative splicing in rice under cold stress. Overall, our work generates a rich resource with broad implications for understanding the genetic basis of cold response mechanisms in plants.


Assuntos
Processamento Alternativo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/fisiologia , Processamento Alternativo/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Temperatura Baixa , Resposta ao Choque Frio/genética , Transcriptoma/genética
2.
Phys Chem Chem Phys ; 26(11): 8716-8723, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38416055

RESUMO

Carbon nanorings have attracted substantial interest from synthetic chemists due to their unique topological structures and distinct physical properties. An intriguing π-conjugated double-nanoring structure, denoted as [8]CPP-[10]cyclacene, was constructed via the integration of [8]cycloparaphenylene ([8]CPP) into [10]cyclacene. Using the external electric field stimuli-responsiveness of [8]CPP-[10]cyclacene, directional charge transfer can be induced, resulting in the emergence of intriguing properties. The effects of the external electric field in three specific directions were explored, vertically in the [8]CPP unit (Fy), vertically in the [10]cyclacene unit (Fz), and horizontally along the double nanorings diameter (Fx). Interestingly, the external electric field vertically to the [10]cyclacene unit significantly enhanced the first hyperpolarizability (ßtot) compared to that vertically to the [8]CPP unit. Notably, [8]CPP-[10]cyclacene under Fx exhibited significantly larger the ßtot values (1.48 × 105 a.u.) than those of vertical Fy and Fz. This work opens up a wide range of nonlinear optics, making it a compelling area to explore in the field of carbon nanomaterials.

3.
Plant Cell Rep ; 43(1): 24, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38150036

RESUMO

KEY MESSAGE: Cold-tolerant QTL qCSS12-regulated 14 hub genes are involved in the chloroplastic biological processes and in the protein synthesis and degradation processes in japonica rice. Low temperature is a main constraint factor for rice growth and production. To better understand the regulatory mechanisms underlying the cold tolerance phenotype in rice, here, we selected a cold-sensitive nearly isogenic line (NIL) NIL(qcss12) as materials to identify hub genes that are mediated by the cold-tolerant locus qCSS12 through weighted gene co-expression network analysis (WGCNA). Fourteen cold-responsive genes were identified, of which, 6 are involved in regulating biological processes in chloroplasts, including the reported EF-Tu, Prk, and ChlD, and 8 are involved in the protein synthesis and degradation processes. Differential expression of these genes between NIL(qcss12) and its controls under cold stress may be responsible for qCSS12-mediated cold tolerance in japonica rice. Moreover, natural variations in 12 of these hub genes are highly correlated with the cold tolerance divergence in two rice subspecies. The results provide deep insights into a better understanding of the molecular basis of cold adaptation in rice and provide a theoretical basis for molecular breeding.


Assuntos
Oryza , Oryza/genética , Cloroplastos , Temperatura Baixa , Resposta ao Choque Frio/genética , Embaralhamento de DNA
4.
Appl Opt ; 61(15): 4486-4493, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256288

RESUMO

Polymer stabilized cholesteric liquid crystal broadband reflective films are prepared by the thermal diffusion of a benzotriazoles organic ultraviolet (UV) absorber (UV-327) combined with photopolymerization. A gradient of UV intensity is established in the direction of film thickness, inducing the formation of a pitch gradient distribution, thus broadening the reflected bandwidth. The effects of UV-327 concentration, UV irradiation intensity, irradiation time, polymerization temperature, and C6M concentration on the reflected bandwidth of the sample are examined in detail. The results indicate that the diffusion method of the organic UV absorber enables the reflected bandwidth to be broadened under appropriate conditions.

5.
Bioelectromagnetics ; 43(2): 106-118, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066900

RESUMO

Numerous studies have shown that radiofrequency electromagnetic radiation (RF-EMR) may negatively affect human health. We detected the effect of 3500 MHz RF-EMR on anxiety-like behavior and the auditory cortex (ACx) in guinea pigs. Forty male guinea pigs were randomly divided into four groups and exposed to a continuous wave of 3500 MHz RF-EMF at an average specific absorption rate (SAR) of 0, 2, 4, or 10 W/kg for 72 h. After exposure, malondialdehyde (MDA) levels, antioxidant enzyme activity, anxiety-like behavior, hearing thresholds, cell ultrastructure, and apoptosis were detected. Our results revealed that hearing thresholds and basic indexes of animal behavior did not change significantly after exposure (P > 0.05). However, the MDA levels of ACx were increased (P < 0.05), and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) activities were decreased (P < 0.05) in the exposure groups compared to the sham group. Ultrastructural changes of ACx, including swollen mitochondria and layered myelin sheaths, were observed. Cytochrome-c relocalization, caspase-9, and cleaved caspase-3 activation were detected in the exposure groups. In conclusion, these results suggest that oxidative stress is an important mechanism underlying the biological effects of RF-EMR, which can induce ultrastructural damage to the ACx and cell apoptosis through a mitochondria-dependent mechanism. Moreover, oxidative stress, apoptosis induction and ultrastructural damage increase in a SAR-dependent manner. However, RF-EMR does not increase hearing thresholds or induce anxiety. Bioelectromagnetics. 43:106-118, 2022. © 2021 Bioelectromagnetics Society.


Assuntos
Córtex Auditivo , Telefone Celular , Animais , Antioxidantes/metabolismo , Ansiedade/etiologia , Córtex Auditivo/metabolismo , Campos Eletromagnéticos/efeitos adversos , Radiação Eletromagnética , Cobaias , Masculino , Estresse Oxidativo
6.
Biochem Biophys Res Commun ; 533(4): 1309-1314, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33051059

RESUMO

Spatial learning and memory are typically assessed to evaluate hippocampus-dependent cognitive and memory functions in vivo. Protein phosphorylation and dephosphorylation by kinases and phosphatases play critical roles in spatial learning and memory. Here we report that the Wip1 phosphatase is essential for spatial learning, with knockout mice lacking Wip1 phosphatase exhibiting dysfunctional spatial cognition. Aberrant phosphorylation of the Wip1 substrates p38, ATM, and p53 were observed in the hippocampi of Wip1-/- mice, but only p38 inhibition reversed impairments in long-term potentiation in Wip1-knockout mice. p38 inhibition consistently ameliorated the spatial learning dysfunction caused by Wip1 deficiency. Our results demonstrate that deletion of Wip1 phosphatase impairs hippocampus-dependent spatial learning and memory, with aberrant downstream p38 phosphorylation involved in this process and providing a potential therapeutic target.


Assuntos
Memória , Proteína Fosfatase 2C/fisiologia , Aprendizagem Espacial , Animais , Hipocampo/enzimologia , Hipocampo/fisiologia , Potenciação de Longa Duração , Masculino , Camundongos Knockout , Teste do Labirinto Aquático de Morris , Fosforilação , Proteína Fosfatase 2C/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Neurochem Res ; 45(5): 1107-1119, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32067150

RESUMO

miR-126 which is considered one of the most important miRNAs for maintaining vascular integrity, plays an important role in neuroprotection after cerebral ischemia-reperfusion (I-R). Moreover, vascular endothelial growth factor A (VEGFA), sprouty-related EVH1 domain-containing protein 1 (SPRED1), and Raf-1 are also involved in physiological processes of vascular endothelial cells (ECs). This study investigated how miR-126 changes with reperfusion time in different brain tissues after global cerebral ischemia and focal cerebral ischemia and examined the underlying mechanism miR-126 involving VEGFA, SPRED1, and Raf-1 after I-R. The results indicated decreases in the levels of miR-126-3p and miR-126-5p expression in mice and gerbils after I-R, consistent with the results after oxygen and glucose deprivation and reperfusion (OGD/R) in PC12 cells. Glial cells were activated as neuronal damage gradually increased after I-R. Inhibition of miR-126-3p exacerbated the OGD/R-induced cell death and reduced cell viability. After miR-126-3p inhibition, the levels of SPRED1 and VEGFA expression were increased, and p-Raf-1 expression was decreased after OGD/R. Moreover, based on the intervention of miR-126-3p inhibition, we found that the expression of p-Raf-1 was significantly increased after the intervention of siSPRED1, while it was not statistically significant after intervention of siVEGFA. The reduction of miR-126 expression after global and focal cerebral ischemia exacerbated neuronal death, which was closely related to increasing the SPRED1 activation and inhibiting the Raf-1 expression.


Assuntos
Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , MicroRNAs/biossíntese , Traumatismo por Reperfusão/metabolismo , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Expressão Gênica , Gerbillinae , Hipocampo/patologia , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/metabolismo , Ataque Isquêmico Transitório/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , MicroRNAs/genética , Células PC12 , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
8.
Clin Exp Pharmacol Physiol ; 46(4): 337-349, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30485484

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder pathologically characterized by the loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). Chronic neuroinflammation is one of the hallmarks of PD pathophysiology. Cathepsin D (CathD), a soluble aspartic protease, has been reported to play an important role in neurodegenerative diseases such as PD. This research focuses on the role of CathD and the molecular mechanisms involved in the process of neuroinflammation and neurotoxicity. We use 1-methyl-4phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-challenged mice and lipopolysaccharide (LPS)-induced murine microglia BV2 cells as the in vivo and in vitro models, respectively. The effect of CathD on the neuroinflammation, cytotoxicity and the underlying mechanisms associated with NF-κB signalling pathway are investigated. Data showed that MPTP induces motor deficit, inflammation and depletion of dopaminergic neurons in PD model mice. Notably, cathD was overexpressed in the SNpc of MPTP-induced PD mice and was highly expressing in LPS-stimulated primary microglial cells and BV-2 cells. Furthermore, knockdown of CathD with lentiviral transduction inhibited LPS-induced neuroinflammation through inhibition of NF-κB signalling pathway primarily by regulating the NF-κB p65 nuclear translocation both in BV-2 and primary microglial cells. Additionally, knockdown of CathD protected the activated-microglia induced dopaminergic neurons MN9D cells from neurotoxicity as well as apoptosis. Our findings bring a new insight into understanding the complex mechanisms underlying the pathogenesis of PD and provide a novel target to attenuate the excessive neuroinflammatory responses in the treatment of PD.

9.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614592

RESUMO

As organelles for photosynthesis in green plants, chloroplasts play a vital role in solar energy capture and carbon fixation. The maintenance of normal chloroplast physiological functions is essential for plant growth and development. Low temperature is an adverse environmental stress that affects crop productivity. Low temperature severely affects the growth and development of plants, especially photosynthesis. To date, many studies have reported that chloroplasts are not only just organelles of photosynthesis. Chloroplasts can also perceive chilling stress signals via membranes and photoreceptors, and they maintain their homeostasis and promote photosynthesis by regulating the state of lipid membranes, the abundance of photosynthesis-related proteins, the activity of enzymes, the redox state, and the balance of hormones and by releasing retrograde signals, thus improving plant resistance to low temperatures. This review focused on the potential functions of chloroplasts in fine tuning photosynthesis processes under low-temperature stress by perceiving stress signals, modulating the expression of photosynthesis-related genes, and scavenging excess reactive oxygen species (ROS) in chloroplasts to survive the adverse environment.


Assuntos
Cloroplastos/metabolismo , Estresse Fisiológico , Viridiplantae/crescimento & desenvolvimento , Ciclo do Carbono , Temperatura Baixa , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Viridiplantae/metabolismo
10.
Cell Physiol Biochem ; 44(1): 133-151, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29130967

RESUMO

BACKGROUND/AIMS: Lung cancer (LC) continues to be one of the most prevalent cancers around the world. During this study we aimed to investigate the involvement of endoplasmic reticulum stress (ERS) in autophagy, apoptosis, and chemotherapy resistance of mutant p53 LC cells. METHODS: Immunohistochemistry was employed to help determine the p53 mutation status of cancer cells from 92 primary LC patients, who were subsequently assigned to either the mutant p53 (n = 39) or wild-type p53 group (n = 53). RESULTS: Mutant p53 cells exhibited increased expression of the C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78), and inositol-requiring enzyme-1α (IRE1α). The Mutant p53 cells were also found to be sensitive to chemotherapy and displayed decreased expression of PI3K, Akt, and mTOR. The mutant p53 cell lines were treated with tunicamycin to induce ERS and rapamycin in order to inhibit mTOR. Both agents increased the expression of CHOP, GRP78, IRE1α, LC3-II/LC3-I, Atg5, Atg7, caspase-3, caspase-12, cleaved caspase-3, cleaved caspase-12, as well as decreases in cell proliferation as well as the expression levels of PI3K, Akt, and mTOR. Enhanced levels of cell apoptosis and reduced chemotherapy resistance were also detected. CONCLUSION: The findings of our study suggest that ERS promotes autophagy and apoptosis, while acting to reduce chemotherapy resistance in mutant p53 LC cells by downregulating the PI3K/Akt/mTOR signaling pathway.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático , Neoplasias Pulmonares/patologia , Proteína Supressora de Tumor p53/genética , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Tunicamicina/farmacologia , Tunicamicina/uso terapêutico
11.
Anal Biochem ; 533: 26-33, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28610874

RESUMO

Positively-charged nylon membrane (NM) is a general solid-phase support for nucleic acid detection due to its convenient immobilization of nucleic acid materials by direct electrostatic adherence and simple UV crosslinking. Rolling circle amplification (RCA) is a widely used isothermal DNA amplification technique for nucleic acid detection. Near-infrared fluorescence (NIRF) is a new fluorescence technique with high sensitivity due to low background. This study developed a simple method for detecting nucleic acid molecules by combining the advantages of NM, RCA and NIRF, named NIRF-based solid phase RCA on nylon membrane (NM-NIRF-sRCA). The detection system of this method only need two kinds of nucleic acid molecules: target-specific probes with a RCA primer (P) at their 3' end and a rolling circle (RC). The detection procedure consists of four steps: (1) immobilizing detected nucleic acids on NM by UV crosslinking; (2) hybridizing NM with specific probes and RC; (3) amplifying by a RCA reaction containing biotin-dUTP; (4) incubating NM with NIRF-labeled streptavidin and imaging with a NIRF imager. The method was fully testified by detecting oligonucleotides, L1 fragments of various HPV subtypes cloned in plasmid, and E.coli genomic DNA. This study thus provides a new facile method for detecting nucleic acid molecules.


Assuntos
Técnicas Biossensoriais , Técnicas de Amplificação de Ácido Nucleico , Ácidos Nucleicos/isolamento & purificação , Biotina/química , Primers do DNA/genética , Humanos , Membranas/química , Hibridização de Ácido Nucleico , Ácidos Nucleicos/genética , Nylons/química , Estreptavidina/química
12.
J Pharmacol Sci ; 128(1): 35-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26003084

RESUMO

Over-activated microglia is involved in various kinds of neurodegenerative process including Parkinson, Alzheimer and HIV dementia. Suppression of microglial over activation has emerged as a novel strategy for treatment of neuroinflammation-based neurodegeneration. In the current study, anti-inflammatory and neuroprotective effects of the ent-kauranoid diterpenoids, which were isolated from the aerial parts of Rabdosia japonica (Burm. f.) var. glaucocalyx (Maxim.) Hara, were investigated in cultured microglia cells. Glaucocalyxin B (GLB), one of five ent-kauranoid diterpenoids, significantly decreased the generation of nitric oxide (NO), tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) in the lipopolysaccharide (LPS)-activated microglia cells. In addition, GLB inhibited activation of nuclear factor-κB (NF-κB), p38 mitogen-activated protein kinase (MAPK) and generation of reactive oxygen species (ROS) in LPS-activated microglia cells. Furthermore, GLB strongly induced the expression of heme oxygenase (HO)-1 in BV-2 microglia cells. Finally, GLB exhibited neuroprotective effect by preventing over-activated microglia induced neurotoxicity in a microglia/neuron co-culture model. Taken together, the present study demonstrated that the GLB possesses anti-nueroinflammatory activity, and might serve as a potential therapeutic agent for treating neuroinflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides , Diterpenos do Tipo Caurano/farmacologia , Microglia/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Fármacos Neuroprotetores , Fitoterapia , Animais , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Diterpenos do Tipo Caurano/isolamento & purificação , Diterpenos do Tipo Caurano/uso terapêutico , Heme Oxigenase-1/metabolismo , Interleucina-1beta/metabolismo , Isodon/química , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/metabolismo , Doenças Neurodegenerativas/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Fator de Necrose Tumoral alfa/metabolismo
13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 32(1): 142-5, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25997282

RESUMO

Skin aging principles play important roles in skin disease diagnosis, the evaluation of skin cosmetic effect, forensic identification and age identification in sports competition, etc. This paper proposes a new method to evaluate the skin aging objectively and quantitatively by skin texture area. Firstly, the enlarged skin image was acquired. Then, the skin texture image was segmented by using the iterative threshold method, and the skin ridge image was extracted according to the watershed algorithm. Finally, the skin ridge areas of the skin texture were extracted. The experiment data showed that the average areas of skin ridges, of both men and women, had a good correlation with age (the correlation coefficient r of male was 0.938, and the correlation coefficient r of female was 0.922), and skin texture area and age regression curve showed that the skin texture area increased with age. Therefore, it is effective to evaluate skin aging objectively by the new method presented in this paper.


Assuntos
Envelhecimento da Pele , Algoritmos , Feminino , Humanos , Masculino , Pele
14.
Anal Chem ; 86(5): 2572-9, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24475783

RESUMO

This study describes a method for analyzing transcription factor (TF) activity, near-infrared fluorescent solid-phase rolling circle amplification (NIRF-sRCA). This method analyzes TF activity in four steps: (i) incubate DNA with protein sample and isolate TF-bound DNA, (ii) hybridize the TF-bound DNA and rolling circle to DNA microarray, (iii) amplify the TF-bound DNA with sRCA that contains biotin-labeled dUTP, and (iv) detect sRCA products by binding of NIRF-labeled streptavidin and NIRF imaging. This method was validated by proof-of-concept detection of purified TF protein and cell nuclear extract. Detection of purified TF protein demonstrated that NIRF-sRCA could quantitatively detect NF-κB p50 protein, and as little as 6.94 ng (∼140 fmol) of this protein was detected. Detection of nuclear extract revealed that NIRF-sRCA could specifically and quantitatively detect NF-κB p50 activity in HeLa cell nuclear extracts, and the activity of this TF in as little as 0.625 µg of nuclear extracts could be detected. Detection of nuclear extract also revealed that NIRF-sRCA could detect the relative activities of multiple TFs in HeLa cell nuclear extracts and the fold induction of multiple TFs in the TNFα-induced HeLa cell nuclear extracts. Therefore, this study provides a new tool for studying TFs.


Assuntos
Espectrometria de Fluorescência/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Fatores de Transcrição/análise , Células HeLa , Humanos , Limite de Detecção , NF-kappa B/análise , Proteínas Recombinantes/análise
15.
Tumour Biol ; 35(12): 11809-17, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25344211

RESUMO

Although there have been substantial advances in our knowledge of the resistance of diffuse large B cell lymphoma (DLBCL) to chemotherapy, there are few efficient treatment strategies for recurrent/refractory DLBCL. The aim of this study was to investigate the role of aldehyde dehydrogenase (ALDH) 1A1 in the resistance of diffuse large B cell lymphoma to the chemotherapeutic mixture consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). The involvement of ALDH1A1 in DLBCL was elucidated by knockdown and pharmacologic inhibition; Cell Counting Kit-8 (CCK-8) and clone formation assays were used to determine its role in CHOP sensitivity and clone formation ability. Caspase colorimetric assay was used to measure the extent of apoptosis. Western blot analysis was used to measure signal transducer and activator of transcription 3 (STAT3)/nuclear factor kappa B (NF-κB) signaling proteins, and quantitative real-time PCR (RT-PCR) was used to measure the differential expression of ALDH1A1 of DLBCL patients and healthy donors. ALDH1A1 showed a 5.64-fold higher expression in malignant B cells than in normal B cells. Diethylaminobenzaldehyde (DEAB) decreased the half maximal inhibitory concentration (IC50) of the CHOP regimen in Farage cells from 344.78 ± 65.75 to 183.88 ± 49.75 ng/ml (P = 0.004). Both knockdown and inhibition of ALDH1A1 reduced clonogenicity, increased caspase-3/caspase-9 activity, and attenuated the phosphorylation status of STAT3/NF-κB. The prognosis of patients with a high level of ALDH1A1 expression was poor compared with that of patients with low levels of expression (P = 0.044). ALDH1A1 is a new mediator for resistance of DLBCL to CHOP; it is a predictor of clinical prognosis and may serve as a potential target to improve chemotherapy responsiveness of human DLBCL.


Assuntos
Aldeído Desidrogenase/genética , Resistencia a Medicamentos Antineoplásicos/genética , Linfoma Difuso de Grandes Células B/genética , Adulto , Idoso , Aldeído Desidrogenase/metabolismo , Família Aldeído Desidrogenase 1 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Ativação Enzimática/genética , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Estadiamento de Neoplasias , Prednisona/uso terapêutico , Prognóstico , Interferência de RNA , Retinal Desidrogenase , Fator de Transcrição STAT3/metabolismo , Ensaio Tumoral de Célula-Tronco , Vincristina/uso terapêutico , Adulto Jovem
16.
Environ Sci Technol ; 48(2): 920-9, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24377871

RESUMO

Seasonal changes in arsenic and iron accumulation rates were examined in the sediments of a brook that receives groundwater discharges of arsenic and reduced iron. Clean glass bead columns were deployed in sediments for known periods over the annual hydrologic cycle to monitor changes in arsenic and iron concentrations in bead coatings. The highest accumulation rates occurred during the dry summer period (July-October) when groundwater discharges were likely greatest at the sample locations. The intermediate flow period (October-March), with higher surface water levels, was associated with losses of arsenic and iron from bead column coatings at depths below 2-6 cm. Batch incubations indicated iron releases from solids to be induced by biological reduction of iron (oxy)hydroxide solids. Congruent arsenic releases during incubation were limited by the high arsenic sorption capacity (0.536 mg(As)/mg(Fe)) of unreacted iron oxide solids. The flooded spring (March-June) with high surface water flows showed the lowest arsenic and iron accumulation rates in the sediments. Comparisons of accumulation rates across a shoreline transect were consistent with greater rates at regions exposed above surface water levels for longer times and greater losses at locations submerged below surface water. Iron (oxy)hydroxide solids in the shallowest sediments likely serve as a passive barrier to sorb arsenic released to pore water at depth by biological iron reduction.


Assuntos
Arsênio/análise , Sedimentos Geológicos/química , Água Subterrânea/química , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise , Adsorção , Biodegradação Ambiental , Congelamento , Ferro/análise , New Hampshire
17.
Biol Pharm Bull ; 37(8): 1282-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25087950

RESUMO

Microglia activation-mediated neuroinflammation plays an important role in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and human immunodeficiency virus (HIV)-associated dementia. Inhibition of microglia activation may alleviate neurodegeneration under neuroinflammatory conditions. In the present study, we compared three flavone C-glycosides extracted from Trollius chinensis BUNGE using a cell-based assay to evaluate their antiinflammatory effects on microglial cells. The results showed that orientin-2"-O-galactopyranoside (OGA) significantly inhibited the production of nitric oxide and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-stimulated microglial cells. OGA also markedly inhibited the LPS-induced expression of TNF-α, interleukin-1ß, inducible nitric oxide (NO) synthase, and cyclooxygenase-2, which was accompanied by suppression of the activation of nuclear factor (NF)-κB and the extracellular signal-regulated kinase (ERK) signal pathway. In addition, OGA decreased LPS-induced reactive oxygen species generation, which appears to be related to the activation of the NF-E2-related factor2 (NRF2)/ heme oxygenase-1 (HO-1) pathway in BV-2 microglial cells. Furthermore, OGA reduced the cytotoxicity of activated microglia toward HT-22 neuroblastoma cells in a co-culture system. Taken together, the present study demonstrated that the induction of HO-1-mediated inhibition of the NF-κB and ERK pathways contributes significantly to the antineuroinflammatory and neuroprotective effects elicited by OGA.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonas/farmacologia , Galactosídeos/farmacologia , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Heme Oxigenase-1/genética , Interleucina-1beta/genética , Lipopolissacarídeos , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Ratos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
18.
Can J Microbiol ; 60(5): 277-86, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24749954

RESUMO

We investigated the seasonal and spatial variation in activity and density of the metabolically active in situ microbial community (AIMC) at a landfill leachate-impacted groundwater - surface water interface (GSI). A series of AIMC traps were designed and implemented for AIMC sampling and microbial activity and density examinations. Measurements were made not only at the level of bacterial domain but also at the levels of alphaproteobacterial Rhizobiales order and gammaproteobacterial Pseudomonas genus, both of which included a large number of iron-oxidizing bacteria as revealed from previous analysis. Consistently higher microbial activities with less variation in depth were measured in the AIMC traps than in the ambient sediments. Flood disturbance appeared to control AIMC activity distributions at the gradually elevated GSI. The highest AIMC activities were generally obtained from locations closest to the free surface water boundary except during the dry season when microbial activities were similar across the entire GSI. A clone library of AIMC 16S rRNA genes was constructed, and it confirmed the predominant role of the targeted alphaproteobacterial group in AIMC activity and composition. This taxon constituted 2%-14% of all bacteria with similar activity distribution profiles. The Pseudomonas group occupied only 0.1‰-0.5‰ of the total bacterial density, but its activity was 27 times higher than the bacterial average. Of the 16S rRNA sequences in the AIMC clone library, 7.5% were phylogenetically related to putative IOB, supporting the occurrence and persistence of active microbial iron oxidation across the studied iron-rich GSI ecosystem.


Assuntos
Bactérias/isolamento & purificação , Água Subterrânea/microbiologia , Microbiologia da Água , Alphaproteobacteria/classificação , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Alphaproteobacteria/metabolismo , Bactérias/classificação , Bactérias/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/metabolismo , Ferro/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Estações do Ano , Poluentes Químicos da Água
19.
PeerJ ; 11: e16405, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034868

RESUMO

Background: Recent studies suggest machine learning represents a promising predictive option for patients in intensive care units (ICU). However, the machine learning performance regarding its actual predictive value for early detection in acute kidney injury (AKI) patients remains uncertain. Objective: This study represents the inaugural meta-analysis aiming to investigate the predictive value of machine learning for assessing the risk of AKI among ICU patients. Methods: PubMed, Web of Science, Embase, and the Cochrane Library were all thoroughly searched from inception to June 25, 2022. Eligible studies for inclusion were those concentrating on the predictive value and the development, validation, or enhancement of a prediction model for AKI patients in the ICU. Measures of effects, including c-index, sensitivity, specificity, and their corresponding 95% confidence intervals (CIs), were employed for analysis. The risk of bias in the included original studies was assessed using Probst. The meta-analysis in our study was carried out using R version 4.2.0. Results: The systematic search yielded 29 articles describing 13 machine-learning models, including 86 models in the training set and 57 in the validation set. The overall c-index was 0.767 (95% CI [0.746, 0.788]) in the training set and 0.773 (95% CI [0.741, 0.804]) in the validation set. The sensitivity and specificity of included studies are as follows: sensitivity [train: 0.66 (95% CI [0.59, 0.73]), validation: 0.73 (95% CI [0.68, 0.77])]; and specificity [train: 0.83 (95% CI [0.78, 0.87])], validation: 0.75 (95% CI [0.71, 0.79])]. Conclusion: The machine learning-based method for predicting the risk of AKI in hospital ICU patients has excellent predictive value and could potentially serve as a prospective application strategy for early identification. PROSPERO Registration number ID: CRD42022362838.


Assuntos
Injúria Renal Aguda , Humanos , Injúria Renal Aguda/diagnóstico , Sensibilidade e Especificidade , Unidades de Terapia Intensiva , Hospitais , Aprendizado de Máquina
20.
J Hazard Mater ; 443(Pt A): 130164, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36308938

RESUMO

This study proposed the fluidization-like dielectric barrier discharge (DBD) plasma for the remediation of lindane contaminated soil and integrated physical and chemical reaction pathway. Soil particle distribution within the reactor was simulated with Euler-Euler and Gidaspow drag models, and a bipolar pulsed power supply was applied to energize the DBD reactor after full fluidized. The effect of soil particles movement on electric features was discussed in terms of voltage waveforms and Lissajous figures. Lindane degradation was found to be related to electrics parameters and soil properties. Soil samples before and after treatment were analyzed by XRD and SEM methods. A 95.98% lindane decomposition and 0.66 mgLindane/h average reaction rate were obtained with 3 wt% CaO injection by pulse power drove fluidization-like DBD after 32 min treatment. Ozone was proved to play a major role during lindane degrading by plasma. The reaction potential pathway of lindane decomposition contains 4 steps, including dehydrogen, dehydrochlorination, and dechlorination, respectively.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Hexaclorocicloexano/química , Poluentes do Solo/química , Solo , Poluição Ambiental
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA