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1.
Analyst ; 149(10): 2996-3007, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38602375

RESUMO

Electrical insulators used in transmission lines and outdoor substations are exposed to severe environmental pollution, which significantly increases the risk of power system failure, especially when the pollution layer is highly humid due to adverse weather conditions. The focus of this paper is to establish an effective method for assessing the moisture content (MC) in pollution layers as it serves as a crucial indicator for evaluating the risk of failure in insulators. Hyperspectral imaging (HSI) technology with a spectral range of 371.08-1037.89 nm was applied to determine significant changes in reflectance spectral characteristics in insulators during dynamic wetting and drying periods. Partial least squares regression (PLSR) models were utilized to evaluate the data presentation enhancement abilities of spectral transformation models and the data dimensionality reduction abilities of characteristic band selection methods. Furthermore, PLSR models were developed to calculate the MC along the pixel dimension to visually retrieve the dynamic wetting and drying processes of the pollution layer. The R-squared and root-mean-square error (RMSE) results in the cross-verification set and prediction set of the RE-RF(70%)-PLSR model with two characteristic bands with a wavelength of 543.28 nm and 848.01 nm were as follows: RCV2 = 0.9824, RMSECV = 0.0367, RP2 = 0.9818, RMSEP = 0.0369, respectively. This research contributes towards the visualization retrieval of the MC and offers an important technique for analyzing flashover evolution, optimizing insulator design, and preparing coating materials for insulators.

2.
BMC Musculoskelet Disord ; 25(1): 45, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200474

RESUMO

BACKGROUND: Alamandine is a newly characterized peptide of renin angiotensin system. Our study aims to investigate the osteo-preservative effects of alamandine, explore underlying mechanism and bring a potential preventive strategy for postmenopausal osteoporosis in the future. METHODS: An ovariectomy (OVX)-induced rat osteoporosis model was established for in vivo experiments. Micro-computed tomography and three-point bending test were used to evaluate bone strength. Histological femur slices were processed for immunohistochemistry (IHC). Bone turnover markers and nitric oxide (NO) concentrations in serum were determined with enzyme-linked immunosorbent assay (ELISA). The mouse embryo osteoblast precursor (MC3T3-E1) cells were used for in vitro experiments. The cell viability was analysed with a Cell Counting Kit­8. We performed Alizarin Red S staining and alkaline phosphatase (ALP) activity assay to observe the differentiation status of osteoblasts. Western blotting was adopted to detect the expression of osteogenesis related proteins and AMP-activated protein kinase/endothelial nitric oxide synthase (AMPK/eNOS) in osteoblasts. DAF-FM diacetate was used for semi-quantitation of intracellular NO. RESULTS: In OVX rats, alamandine alleviated osteoporosis and maintained bone strength. The IHC showed alamandine increased osteocalcin and collagen type I α1 (COL1A1) expression. The ELISA revealed alamandine decreased bone turnover markers and restored NO level in serum. In MC3T3-E1 cells, alamandine promoted osteogenic differentiation. Western blotting demonstrated that alamandine upregulated the expression of osteopontin, Runt-related transcription factor 2 and COL1A1. The intracellular NO was also raised by alamandine. Additionally, the activation of AMPK/eNOS axis mediated the effects of alamandine on MC3T3-E1 cells and bone tissue. PD123319 and dorsomorphin could repress the regulating effect of alamandine on bone metabolism. CONCLUSION: Alamandine attenuates ovariectomy-induced osteoporosis by promoting osteogenic differentiation via AMPK/eNOS axis.


Assuntos
Oligopeptídeos , Osteogênese , Osteoporose , Camundongos , Feminino , Animais , Ratos , Proteínas Quinases Ativadas por AMP , Óxido Nítrico Sintase Tipo III , Microtomografia por Raio-X , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/prevenção & controle
3.
J Med Virol ; 95(1): e28139, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36089764

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused extensive loss of life worldwide. Further, the COVID-19 and influenza mix-infection had caused great distress to the diagnosis of the disease. To control illness progression and limit viral spread within the population, a real-time reverse-transcription PCR (RT-PCR) assay for early diagnosis of COVID-19 was developed, but detection was time-consuming (4-6 h). To improve the diagnosis of COVID-19 and influenza, we herein developed a recombinase polymerase amplification (RPA) method for simple and rapid amplification of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19 and Influenza A (H1N1, H3N2) and B (influenza B). Genes encoding the matrix protein (M) for H1N1, and the hemagglutinin (HA) for H3N2, and the polymerase A (PA) for Influenza B, and the nucleocapsid protein (N), the RNA-dependent-RNA polymerase (RdRP) in the open reading frame 1ab (ORF1ab) region, and the envelope protein (E) for SARS-CoV-2 were selected, and specific primers were designed. We validated our method using SARS-CoV-2, H1N1, H3N2 and influenza B plasmid standards and RNA samples extracted from COVID-19 and Influenza A/B (RT-PCR-verified) positive patients. The method could detect SARS-CoV-2 plasmid standard DNA quantitatively between 102 and 105 copies/ml with a log linearity of 0.99 in 22 min. And this method also be very effective in simultaneous detection of H1N1, H3N2 and influenza B. Clinical validation of 100 cases revealed a sensitivity of 100% for differentiating COVID-19 patients from healthy controls when the specificity was set at 90%. These results demonstrate that this nucleic acid testing method is advantageous compared with traditional PCR and other isothermal nucleic acid amplification methods in terms of time and portability. This method could potentially be used for detection of SARS-CoV-2, H1N1, H3N2 and influenza B, and adapted for point-of-care (POC) detection of a broad range of infectious pathogens in resource-limited settings.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Ácidos Nucleicos , Humanos , COVID-19/diagnóstico , Influenza Humana/diagnóstico , SARS-CoV-2/genética , Recombinases , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Sensibilidade e Especificidade , Nucleotidiltransferases , RNA , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/genética
4.
Acta Pharmacol Sin ; 44(12): 2432-2444, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37507430

RESUMO

Polycystic ovary syndrome (PCOS) is a disorder with endocrinal and metabolic problems in reproductive aged women. Evidence shows that PCOS is in a high prone trend to develop kidney diseases. In this study, we investigated the mediators responsible for PCOS-related kidney injury. We found that tumor necrosis factor (TNF-α) levels were significantly increased in serum and primary cultured granulosa cells (GCs) from PCOS patients. Serum TNF-α levels were positively correlated with serum testosterone and luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratio, suggesting its positive role in the severity of PCOS. Serum TNF-α levels were also positively correlated with the levels of urinary KapU, LamU, α1-MU and ß2-MU, the markers for renal tubular cell-derived proteinuria. We established a PCOS mouse model by resection of the right kidney, followed by daily administration of dihydrotestosterone (DHT, 27.5 µg, i.p.) from D7 for 90 days. We found that TNF-α levels were significantly increased in the ovary and serum of the mice, accompanied by increased renal tubular cell apoptosis, inflammation and fibrosis in kidneys. Furthermore, the receptor of TNF-α, tumor necrosis factor receptor 1 (TNFR1), was significantly upregulated in renal tubular cells. We treated human ovarian granulosa-like tumor cells (KGN) with DHT (1 µg/ml) in vitro, the conditioned medium derived from the granulosa cell culture greatly accelerated apoptotic injury in human proximal tubular epithelial cells (HKC-8), which was blocked after knockdown of TNF-α in KGN cells. Furthermore, knockdown of TNFR1 in renal tubular epithelial cells greatly ameliorated cell injury induced by granulosa cell-derived conditioned medium. These results suggest that serum TNF-α plays a key role in mediating inflammation and apoptosis in renal tubular cells associated with PCOS-related kidney injury.


Assuntos
Síndrome do Ovário Policístico , Feminino , Humanos , Camundongos , Animais , Adulto , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , NF-kappa B/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Meios de Cultivo Condicionados/metabolismo , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Inflamação/metabolismo , Rim/metabolismo , Apoptose
5.
BMC Anesthesiol ; 23(1): 357, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919658

RESUMO

BACKGROUND: Tracheobronchomegaly (TBM) is a rare disorder mainly characterized by dilatation and malacia of the trachea and major bronchi with diverticularization. This will be a great challenge for airway management, especially in thoracic surgery requiring one-lung ventilation. Using a laryngeal mask airway and a modified double-lumen Foley catheter (DFC) as a "blocker" may achieve one-lung ventilation. This is the first report introducing this method in a patient with TBM. CASE PRESENTATION: We present a 64-year-old man with TBM receiving left lower lobectomy. Preoperative chest computed tomography demonstrated a prominent tracheobronchial dilation and deformation with multiple diverticularization. The most commonly used double-lumen tube or bronchial blocker could not match the distorted airways. After general anesthesia induction, a 4# laryngeal mask was inserted, through which the modified DFC was positioned in the left main bronchus with the guidance of a fiberoptic bronchoscope. The DFC balloon was inflated with 10 ml air and lung isolation was achieved without any significant air leak during one-lung or two-lung ventilation. However, the collapse of the non-dependent lung was delayed and finally achieved by low-pressure artificial pneumothorax. The surgery was successful and the patient was extubated soon after the surgery. CONCLUSIONS: Using a laryngeal mask airway with a modified double-lumen Foley catheter acted as a bronchial blocker could be an alternative method to achieve lung isolation.


Assuntos
Ventilação Monopulmonar , Traqueobroncomegalia , Masculino , Humanos , Pessoa de Meia-Idade , Intubação Intratraqueal/métodos , Manuseio das Vias Aéreas , Traqueia , Ventilação Monopulmonar/métodos
6.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685945

RESUMO

Holotrichia parallela is an important plant pest. Comparative feeding experiments showed that the egg production, oviposition duration and survival rate of H. parallela beetles were significantly higher when they fed on elm leaves than when they fed on willow or purpus privet leaves. RNA sequencing was used to determine transcriptomic changes associated with oviposition. Comparative transcriptome analysis revealed that the beetles that fed on elm and willow had a total of 171 genes with differential expression. When the beetles fed on elm and purpus privet, 3568 genes had differential expression. The vitellogenesis, ovarian serine protease, odorant-binding proteins, acyl-CoA synthetase and follicle cell proteins were commonly upregulated genes in elm-fed beetles compared with those fed on willow/purpus privet leaves. The involvement of the follicle cell protein 3C gene in the regulation of oviposition was confirmed using RNA interference. The results provide insights into the molecular mechanisms underlying oviposition in H. parallela feeding on different host plants. This study also describes a method for identifying potentially effective genes for pest control.


Assuntos
Clorofíceas , Besouros , Feminino , Animais , Transcriptoma , Oviposição , Perfilação da Expressão Gênica , Besouros/genética
7.
Phys Chem Chem Phys ; 25(1): 759-767, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36508170

RESUMO

The structural phase transition (SPT) and metal-insulator phase transition (MIT) always occur simultaneously upon heating from the low-temperature insulator M1 phase to the high-temperature metal R phase in vanadium dioxide, and it is still unclear which one of Mott correlation and Peierls distortion plays a decisive role in the thermally induced phase transition (PT) since 1959. Our density functional theory (DFT)-based calculations revealed that the intermediate phase in the PT, the so-called monoclinic metal phase, is a zero indirect band gap semimetal (P21/c space group) with a pseudo gap (199 meV). From the M1 phase to the monoclinic metal phase, the band gap decreases gradually to zero, and the bonding lengths between vanadium-vanadium atoms remain nearly constant. The SPT and MIT from the intermediate structure to the R phase occur simultaneously with a sudden change of bonding lengths between vanadium-vanadium atoms, in which electrons can jump down rather than jump up to the conduction band minimum (CBM) from the valence band maximum (VBM) under thermal fluctuation in order to lower the total energy of the system to push forward the occurrence of PT. The electron jumping does not require additional energy from Coulomb repulsion between electrons even though it is always present. This SPT is a typical Peierls PT or a pseudo Mott PT rather than an actual Mott PT in the each of the two stages. Our conclusions provide a new understanding of SPT and MIT in vanadium dioxide that has been debated for more than 80 years.

8.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5574-5583, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36471975

RESUMO

Histone lysine-specific demethylase 1(LSD1) has become a promising molecular target for lung cancer therapy. Upon the screening platform for LSD1 activity, some Chinese herbal extracts were screened for LSD1 activity inhibition, and the underlying mechanism was preliminarily investigated at both molecular and cellular levels. The results of LSD1 inhibition showed that Puerariae Lobatae Radix extract can effectively reduce LSD1 expression to elevate the expression of H3 K4 me2 and H3 K9 me2 substrates in H1975 and H1299 cells. Furthermore, Puerariae Lobatae Radix was evaluated for its anti-lung cancer activity. It had a potent inhibitory ability against the proliferation and colony formation of both H1975 and H1299 cells. Flow cytometry and DAPI staining assays indicated that Puerariae Lobatae Radix can induce the apoptosis of lung cancer cells. In addition, it can significantly suppress the migration and reverse the epithelial-mesenchymal transition(EMT) process of lung cancer cells by activating E-cadherin and suppressing the expression of N-cadherin, slug and vimentin. To sum up, Puerariae Lobatae Radix displayed a robust inhibitory activity against lung cancer, and the mechanism may be related to the down-regulation of LSD1 expression to induce the cell apoptosis and suppress the cell migration and EMT process. These findings will provide new insights into the action of Puerariae Lobatae Radix as an anti-lung cancer agent and offer new ideas for the study on the anti-cancer action of Chinese medicine based on the epigenetic modification.


Assuntos
Neoplasias , Pueraria , Pueraria/química , Histona Desmetilases/genética , Histona Desmetilases/análise , Raízes de Plantas/química , Transição Epitelial-Mesenquimal
9.
Zhongguo Zhong Yao Za Zhi ; 46(22): 5887-5894, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-34951179

RESUMO

This study aims to explore the mechanism of fresh Phragmitis Rhizoma against chronic bronchitis airway inflammation. The SD rats of SPF grade were divided into control group, model group, Guilongkechuanning group(GLKCN, 1.125 g·kg~(-1)), high-dose fresh Phragmitis Rhizoma group(LG-HD, 15 g·kg~(-1)), and low-dose fresh Phragmitis Rhizoma group(LG-LD, 7.5 g·kg~(-1)). The chronic bronchitis models of rats in other groups except the control group were induced by the modified smoking method. From the 15 th day of modeling, the rats were given corresponding agents by gavage for 20 consecutive days. After the last administration, the rats were sacrificed for sample collection. Enzyme-linked immunosorbent assay(ELISA) was employed to detect serum transforming growth factor-ß(TGF-ß) and interleukin-6(IL-6) levels. The protein expression of TGF-ß, IL-1ß and IL-6 in lung tissue was detected by immunohistochemical method. Masson staining was performed to detect collagen fibers and muscle fibers in lung tissue, and HE staining to detect the pathological changes of lung tissue. Human bronchial epithelial(16 HBE) cells were cultured in vitro, and CCK-8(cell counting kit-8) method was used to detect the cytotoxicity of cigarette smoke extract(CSE) and fresh Phragmitis Rhizoma. After the exposure of 16 HBE cells to 3.5% CSE and appropriate concentration(800, 400 µg·mL~(-1)) of fresh Phragmitis Rhizoma for 24 h, quantitative real-time PCR was conducted to determine the mRNA levels of TGF-ß and IL-1ß, and Western blot was employed to determine the protein levels of TGF-ß and IL-6 in the cells. The rat model of chronic bronchitis induced by smoking was successfully established. Fresh Phragmitis Rhizoma reduced serum TGF-ß and IL-6 levels, down-regulated the protein levels of TGF-ß, IL-1ß, and IL-6 in lung tissue, and alleviated pathological changes and fibrotic lesions in lung tissue. Moreover, it down-regulated the CSE-induced protein expression of TGF-ß and IL-6 as well as the mRNA level of TGF-ß in 16 HBE cells. These results indicated that fresh Phragmitis Rhizoma could prevent airway inflammation from chronic bronchitis and promote cell repair by inhibiting the TGF-ß signaling pathway.


Assuntos
Bronquite Crônica , Medicamentos de Ervas Chinesas/farmacologia , Poaceae/química , Animais , Bronquite Crônica/tratamento farmacológico , Bronquite Crônica/genética , Inflamação , Pulmão , Ratos , Ratos Sprague-Dawley , Rizoma , Transdução de Sinais , Fator de Crescimento Transformador beta/genética
10.
BMC Neurosci ; 21(1): 33, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736520

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neuro-degenerative disease with a major manifestation of dementia. MicroRNAs were reported to regulate the transcript expression in patients with Alzheimer's disease (AD). In this study, we investigated the roles of miR-138, a brain-enriched miRNA, in the AD cell model. METHODS: The targets of miRNA-138 was predicted by bioinformatic analysis. The expression levels of DEK at both mRNA and protein levels were determined by qRT-PCR and Western blot, respectively. Luciferase assays were carried out to examine cell viabilities. Hoechst 33258 staining was used to detect cell apoptosis. RESULTS: Our results demonstrated that the expression levels of miR-138 were increased in AD model, and DEK was a target of miR-138. Overexpression of miR-138 in SH-SY5Y cells obviously down-regulated the expression of DEK in SH-SY5Y cells, resulting in the inactivation of AKT and increased expression levels of proapoptotic caspase-3. MiR-138 mediated-suppression of DEK increased the susceptibility of cell apoptosis. CONCLUSIONS: MicroRNA-138 promotes cell apoptosis of SH-SY5Y by targeting DEK in SH-SY5Y AD cell model. The regulation of miR-138 may contribute to AD via down-regulation of the DEK/AKT pathway.


Assuntos
Doença de Alzheimer/genética , Proteínas Cromossômicas não Histona/genética , MicroRNAs/genética , Neuroblastoma/genética , Proteínas Oncogênicas/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Doença de Alzheimer/metabolismo , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/metabolismo , Humanos , Neuroblastoma/metabolismo , Proteínas Oncogênicas/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Transdução de Sinais/genética
11.
Mol Psychiatry ; 24(2): 282-293, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30087452

RESUMO

Hypothalamic neuropeptide orexin has been implicated in the pathophysiology of psychiatric disorders and accumulating clinical evidence indicates a potential link between orexin and depression. However, the exact role of orexin in depression, particularly the underlying neural substrates and mechanisms, remains unknown. In this study, we reveal a direct projection from the hypothalamic orexinergic neurons to the ventral pallidum (VP), a structure that receives an increasing attention for its critical position in rewarding processing, stress responses, and depression. We find that orexin directly excites GABAergic VP neurons and prevents depressive-like behaviors in rats. Two orexin receptors, OX1R and OX2R, and their downstream Na+-Ca2+ exchanger and L-type Ca2+ channel co-mediate the effect of orexin. Furthermore, pharmacological blockade or genetic knockdown of orexin receptors in VP increases depressive-like behaviors in forced swim test and sucrose preference test. Intriguingly, blockage of orexinergic inputs in VP has no impact on social proximity in social interaction test between novel partners, but remarkably strengthens social avoidance under an acute psychosocial stress triggered by social rank. Notably, a significantly increased orexin level in VP is accompanied by an increase in serum corticosterone in animals exposed to acute stresses, including forced swimming, food/water deprivation and social rank stress, rather than non-stress situations. These results suggest that endogenous orexinergic modulation on VP is especially critical for protecting against depressive reactions to stressful events. The findings define an indispensable role for the central orexinergic system in preventing depression by promoting stress resilience.


Assuntos
Depressão/tratamento farmacológico , Orexinas/metabolismo , Orexinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Depressão/fisiopatologia , Modelos Animais de Doenças , Neurônios GABAérgicos/metabolismo , Hipotálamo/metabolismo , Masculino , Neuropeptídeos/metabolismo , Receptores de Orexina/metabolismo , Receptores de Orexina/fisiologia , Ratos , Ratos Sprague-Dawley , Comportamento Social , Estresse Psicológico/metabolismo
12.
Cancer Control ; 27(2): 1073274820922559, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32379490

RESUMO

Gastric cancer (GC) is fifth most frequently diagnosed cancer and second leading cause of cancer in China. More than 80% of GC are diagnosed at an advanced stage due to low uptake rate of invasive screening method. The performance of methylated SFRP2 test was evaluated in 236 plasma samples, including 92 patients with GC, 16 intestinal metaplasia patients, 26 gastric fundic gland polyp patients, 13 small adenoma patients, 39 hyperplastic polyp patients, and 50 control patients. The sensitivity of plasma methylated SFRP2 was compared to serum CEA, CA72-4, CA19-9, and CA242 results in 79 patients with GC. The sensitivities for detecting GC and gastric intestinal metaplasia by methylated SFRP2 test were 60.9% and 56.3% with a specificity of 86.0%. Methylated SFRP2 test had significantly higher positive detection rate for patients with GC than gastric fundic gland polyp, small adenoma, and hyperplastic polyp patients. In 79 patients with GC, the sensitivities of CEA, CA72-4, CA19-9, and CA242 for detecting GC were 22.8%, 16.5%, 12.7%, and 11.4%. In comparison, the sensitivity of methylated SFRP2 test for detecting GC was 58.2%. Plasma methylated SFRP2 test may become a valuable tool for the noninvasive detection of GC and precursor lesions and showed higher sensitivity than serum tumor markers.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Detecção Precoce de Câncer/métodos , Proteínas de Membrana/genética , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Glicosídicos Associados a Tumores/metabolismo , Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/metabolismo , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Humanos , Masculino , Proteínas de Membrana/sangue , Proteínas de Membrana/química , Pessoa de Meia-Idade , Curva ROC , Neoplasias Gástricas/sangue , Neoplasias Gástricas/genética , Adulto Jovem
13.
Plant Cell ; 28(1): 55-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26721863

RESUMO

Nuclear-localized RNA binding proteins are involved in various aspects of RNA metabolism, which in turn modulates gene expression. However, the functions of nuclear-localized RNA binding proteins in plants are poorly understood. Here, we report the functions of two proteins containing RNA recognition motifs, RZ-1B and RZ-1C, in Arabidopsis thaliana. RZ-1B and RZ-1C were localized to nuclear speckles and interacted with a spectrum of serine/arginine-rich (SR) proteins through their C termini. RZ-1C preferentially bound to purine-rich RNA sequences in vitro through its N-terminal RNA recognition motif. Disrupting the RNA binding activity of RZ-1C with SR proteins through overexpression of the C terminus of RZ-1C conferred defective phenotypes similar to those observed in rz-1b rz-1c double mutants, including delayed seed germination, reduced stature, and serrated leaves. Loss of function of RZ-1B and RZ-1C was accompanied by defective splicing of many genes and global perturbation of gene expression. In addition, we found that RZ-1C directly targeted FLOWERING LOCUS C (FLC), promoting efficient splicing of FLC introns and likely also repressing FLC transcription. Our findings highlight the critical role of RZ-1B/1C in regulating RNA splicing, gene expression, and many key aspects of plant development via interaction with proteins including SR proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Precursores de RNA/metabolismo , Splicing de RNA/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Núcleo Celular/metabolismo , Cromatina/metabolismo , Genes de Plantas , Pleiotropia Genética , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Dados de Sequência Molecular , Mutação/genética , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas com Motivo de Reconhecimento de RNA/química , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Nicotiana/citologia , Transcrição Gênica , Transcriptoma/genética
14.
J Nanosci Nanotechnol ; 18(1): 359-367, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29768854

RESUMO

The technique of the anisotropic wet chemical etching had turned into one of the widely used processes for manufacturing the functional materials in microelectromechanical systems. To better understand the issues of growth mechanisms for the characteristic surface morphologies during an anisotropic chemical etching, in this study the formation and evolution of surface structures were investigated by numerical simulation methods. A chemical etching model was established on the basis of chemical reaction and atomic diffusion. Affecting by the anisotropy of the crystalline structure and etching rate, various featured surface morphologies, including the rippling surface, cusp-like hillock, and nano-pyramid, were numerically developed in accordance with the etching conditions. These characteristic structures were also in well agreements with the corresponding experiments. From the theoretical point of view, the surface morphologies were critically influenced by the kinetic factors of the anisotropic etching rate and the atomic diffusion. With the enhancement of theoretical work in the formation mechanism for the anisotropic chemical etching, the practical technique would possess a more competitive advantage for the wide applications in the fields of the functional materials fabrication.

15.
J Nanosci Nanotechnol ; 18(6): 3982-3990, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442734

RESUMO

Formaldehyde (HCHO) is a main indoor pollutant that is capable of harming the health of residents. Here, we fabricated a novel MnO2/MWCNTs nanocomposite film for non-photocatalytic, room temperature removal of indoor HCHO. MnO2/MWCNTs nanocomposites with various amounts of a-MWCNTs, which were fabricated by a co-precipitation method, were assembled into composite films using vacuum filtration and solvent evaporation. Structural analysis confirms that MnO2 nanoparticles are homogeneously distributed on a-MWCNTs. The acetyl acetone method was used to characterize the catalytic activity of MnO2/MWCNTs nanocomposites. The results show that MnO2/MWCNTs composites with 30 wt% a-MWCNTs present the highest catalytic activity due to a highly active surface. The catalytic activity of MnO2/MWCNTs composite film was characterized in a glovebox at room temperature and showed good removal of HCHO. This study suggests that supporting catalysts on MWCNTs and then assembling them into fibers (1D), films (2D) or aerogels (3D) is a worthwhile approach to promote catalytic activity and prevent dust pollution.

16.
Proc Natl Acad Sci U S A ; 112(39): 12181-6, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26374838

RESUMO

There is a great demand for precisely quantitating the expression of genes of interest in synthetic and systems biotechnology as new and fascinating insights into the genetics of streptomycetes have come to light. Here, we developed, for the first time to our knowledge, a quantitative method based on flow cytometry and a superfolder green fluorescent protein (sfGFP) at single-cell resolution in Streptomyces. Single cells of filamentous bacteria were obtained by releasing the protoplasts from the mycelium, and the dead cells could be distinguished from the viable ones by propidium iodide (PI) staining. With this sophisticated quantitative method, some 200 native or synthetic promoters and 200 ribosomal binding sites (RBSs) were characterized in a high-throughput format. Furthermore, an insulator (RiboJ) was recruited to eliminate the interference between promoters and RBSs and improve the modularity of regulatory elements. Seven synthetic promoters with gradient strength were successfully applied in a proof-of-principle approach to activate and overproduce the cryptic lycopene in a predictable manner in Streptomyces avermitilis. Our work therefore presents a quantitative strategy and universal synthetic modular regulatory elements, which will facilitate the functional optimization of gene clusters and the drug discovery process in Streptomyces.


Assuntos
Produtos Biológicos/isolamento & purificação , Descoberta de Drogas/métodos , Citometria de Fluxo/métodos , Proteínas de Fluorescência Verde/metabolismo , Elementos Reguladores de Transcrição/genética , Streptomyces/química , Biologia Sintética/métodos , Sítios de Ligação/genética , Produtos Biológicos/análise , Descoberta de Drogas/tendências , Microscopia Confocal , Família Multigênica/genética , Regiões Promotoras Genéticas/genética , Propídio , Biologia Sintética/tendências
17.
Apoptosis ; 22(5): 608-625, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28205128

RESUMO

Myocardial ischemia and reperfusion (MIR) results in cardiomyocyte apoptosis with severe outcomes, which blocks cardiac tissue recovering from myocardial ischemia diseases. Heat shock protein 70 (HSP70) is one of protective molecule chaperones which could regulate the nucleus translocation of other proteins. In addition, eukaryotic elongation factor 2 (eEF2), which modulates protein translation process, is vital to the recovery of heart during MIR. However, the relationship between HSP70 and eEF2 and its effects on MIR are unclear. The expression and relationship between HSP70 and eEF2 is confirmed by western blot, immunoprecipitation in vitro using cardiomyocyte cell line H9c2 and in vivo rat MIR model. The further investigation was conducted in H9c2 cells with detection for cell-cycle and apoptosis. It is revealed that eEF2 interacted and be regulated by HSP70, which kept eEF2 as dephosphorylated status and preserved the function of eEF2 during MIR. In addition, HSP70 suppressed the nucleus translocation of phosphorylated eEF2, which inhibited cardiomyocyte apoptosis during myocardial reperfusion stage. Furthermore, HSP70 also interacted with C-terminal fragment of eEF2, which could reverse the nucleus translocation and cardiomyocyte apoptosis caused by N-terminal fragment of eEF2. HSP70 draw on advantage and avoid defect of MIR through regulating phosphorylation and nucleus translocation of eEF2.


Assuntos
Apoptose/genética , Quinase do Fator 2 de Elongação/genética , Proteínas de Choque Térmico HSP70/genética , Traumatismo por Reperfusão Miocárdica/genética , Animais , Transporte Biológico/genética , Linhagem Celular , Núcleo Celular/genética , Regulação da Expressão Gênica/genética , Humanos , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Fosforilação , Ratos , Sumoilação
18.
J Surg Res ; 213: 46-50, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601331

RESUMO

BACKGROUND: The incidence of delayed gastric emptying (DGE) after esophagectomy is 10%-50%, which can interfere with postoperative recovery in the short-term and result in poor quality of life in the long term. Pyloric drainage is routinely performed to prevent DGE, but its role is highly controversial. The aim of this study was to report the rate of DGE after esophagectomy without pyloric drainage and to investigate its risk factors and the potential effect on recovery. MATERIALS AND METHODS: Between January 2010 and January 2015, we analyzed 285 consecutive patients who received an esophagectomy without pyloric drainage. Possible correlations between the incidence of DGE and its potential risk factors were examined in univariate and multivariate analyses, respectively. The outcomes of DGE were reviewed with a follow-up of 3 mo. RESULTS: The overall rate of DGE after esophagectomy was 18.2% (52/285). Among perioperative factors, gastric size (gastric tube versus the whole stomach) was the only significant factor affecting the incidence of DGE in the univariate analysis. The patients who received a whole stomach as an esophageal substitute were more likely to develop DGE than were patients with a gastric tube (13.2% versus 22.4%; P = 0.05). No independent risk factor for DGE was found in the multivariate analysis. The incidence of major postoperative complications, including anastomotic leak, respiratory complications, and cardiac complications, was also not significantly different between both groups, with or without DGE. Within 3 mo of follow-up, most patients could effectively manage their DGE through medication (39/52) or endoscopic pyloric dilation (12/52), with only one patient requiring surgical intervention. CONCLUSIONS: In our study, the overall incidence of DGE is about 20% for patients undergoing esophagectomy without pyloric drainage. Compared with prior findings, this does not result in a significantly increased incidence of DGE. In patients with symptoms of DGE after esophagectomy, prokinetic agents and endoscopic balloon dilation of the pylorus can be effective, as indicated by the high success rate and lack of significant complications.


Assuntos
Drenagem , Esofagectomia/métodos , Gastroparesia/etiologia , Complicações Pós-Operatórias/etiologia , Piloro/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Gastroparesia/epidemiologia , Gastroparesia/terapia , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Fatores de Risco , Resultado do Tratamento
19.
Curr Microbiol ; 74(8): 921-929, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28516199

RESUMO

Calmodulin (CaM) is a Ca2+-binding protein that plays a role in several Ca2+ signaling pathways, which dynamically regulates the activities of hundreds of proteins. The ice alga Chlamydomonas sp. ICE-L, which has the ability to adapt to extreme polar conditions, is a crucial primary producer in Antarctic ecosystem. This study hypothesized that Cam helps the ICE-L to adapt to the fluctuating conditions in the polar environment. It first verified the overall length of Cam, through RT-PCR and RACE-PCR, based on partial Cam transcriptome library of ICE-L. Then, the nucleotide and predicted amino acid sequences were, respectively, analyzed by various bioinformatics approaches to gain more insights into the computed physicochemical properties of the CaM. Potential involvements of Cam in responding to certain stimuli (i.e., UVB radiation, high salinity, and temperature) were investigated by differential expression, measuring its transcription levels by means of quantitative RT-PCR. Results showed that CaM was indeed inducible and regulated by high UVB radiation, high salinity, and nonoptimal temperature conditions. Different conditions had different expression tendencies, which provided an important basis for investigating the adaptation mechanism of Cam in ICE-L.


Assuntos
Calmodulina/análise , Calmodulina/genética , Chlamydomonas/enzimologia , Perfilação da Expressão Gênica , Regiões Antárticas , Calmodulina/química , Chlamydomonas/efeitos dos fármacos , Chlamydomonas/genética , Chlamydomonas/efeitos da radiação , Clonagem Molecular , Biologia Computacional , Pressão Osmótica , Reação em Cadeia da Polimerase , Salinidade , Temperatura , Raios Ultravioleta
20.
Korean J Parasitol ; 55(1): 15-20, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28285502

RESUMO

The aim of this study was to identify antigens for a vaccine or drug target to control rabbit coccidiosis. A combination of 2-dimensional electrophoresis, immunoblotting, and mass spectrometric analysis were used to identify novel antigens from the sporozoites of Eimeria stiedae. Protein spots were recognized by the sera of New Zealand rabbits infected artificially with E. stiedae. The proteins were characterized by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF/TOF-MS) analysis in combination with bioinformatics. Approximately 868 protein spots were detected by silver-staining, and a total of 41 immunoreactive protein spots were recognized by anti-E. stiedae sera. Finally, 23 protein spots were successfully identified. The proteins such as heat shock protein 70 and aspartyl protease may have potential as immunodiagnostic or vaccine antigens. The immunoreactive proteins were found to possess a wide range of biological functions. This study is the first to report the proteins recognized by sera of infected rabbits with E. stiedae, which might be helpful in identifying potential targets for vaccine development to control rabbit coccidiosis.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/análise , Antígenos de Protozoários/imunologia , Coccidiose/veterinária , Eimeria/imunologia , Proteoma/análise , Vacinas Protozoárias/isolamento & purificação , Animais , Coccidiose/imunologia , Coccidiose/prevenção & controle , Biologia Computacional , Eletroforese em Gel Bidimensional , Immunoblotting , Espectrometria de Massas , Vacinas Protozoárias/imunologia , Coelhos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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