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1.
Dalton Trans ; 52(27): 9406-9413, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37358333

RESUMO

Polyoxometalate-based metal-organic frameworks (POMOFs) have received wide attention in supercapacitors and H2O2 detection due to their possession of the rich redox active sites of polyoxometalates (POMs) and the ordered structure of metal-organic frameworks (MOFs). In this study, we successfully synthesized a host-guest Cu3[P2W18O62]@HKUST-1 (HRBNU-7) compound by a grinding method. Cu3[P2W18O62] successfully entered the HKUST-1 pores as confirmed by the results of infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The specific capacitance of HRBNU-7 is 318.6 F g-1 at 1 A g-1 in a three-electrode system using nickel foam as the collector. The specific capacity retention is 92.36% after 5000 cycles. The assembled symmetrical supercapacitor (SSC) achieved a high energy density of 10.58 W h kg-1 at a power density of 500.00 W kg-1. In addition, HRBNU-7 exhibits excellent electrochemical detection of H2O2, including a wide linear range of 0.5 µM-0.3 mM, a low detection limit of 0.17 µM, and excellent selectivity and stability, and it can be effectively utilized for the analysis of H2O2 content in actual serum samples. These excellent properties are attributed to the unique redox activity of Cu3[P2W18O62] and the high specific surface area of HKUST-1. This work offers a strategy for exploring POMOFs as electrode materials in supercapacitors and electrochemical sensors.

2.
Ann Transl Med ; 10(16): 909, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36111049

RESUMO

Background: Intracranial atherosclerotic stenosis (ICAS) is one of the leading causes of stroke worldwide. Current diagnostic evaluations and treatments remain insufficient to assess the vulnerability of intracranial plaques and reduce the recurrence of stroke in symptomatic ICAS. On the other hand, asymptomatic ICAS is associated with an increased risk of cognitive impairment. The pathogenesis of ICAS related cognitive decline is largely unknown. The aim of SICO-ICAS study (stroke incidence and cognitive outcomes of ICAS) is to elucidate the pathophysiology of stroke and cognitive impairment in ICAS population, comprehensively evaluating the complex interactions among life-course exposure, genomic variation, vascular risk factors, cerebrovascular burden and coexisting neurodegeneration. Methods: SICO-ICAS is a multicenter, prospective, observational cohort study. We aim to recruit 3,000 patients with symptomatic or asymptomatic ICAS (>50% or occlusion) who will be followed up for ≥12 months. All participants will undergo pre-designed magnetic resonance imaging packages, blood biomarkers testing, as well as detailed cognitive domains assessment. All participants will undergo clinical visits every 6 months and telephone interviews every 3 months. The primary outcome measurement is ischemic stroke or cognitive impairment within 12 months after enrollment. Discussion: This study will establish a large prospective ICAS cohort, hopefully discover new biomarkers associated with vulnerable intracranial plaques, identify subjects at high risk for incident ischemic stroke or cognitive impairment, and eventually propose a precise diagnostic and treatment strategy for ICAS population. Trial Registration: Chinese Clinical Trials Register ChiCTR2200061938.

3.
Front Med (Lausanne) ; 9: 836012, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510252

RESUMO

Background: Hemangioblastoma-like clear cell stromal tumor (HLCCST) is a recently reported neoplasm of the lung. Only 13 cases have been reported in four recent studies. Because HLCCST is very rare, it has not been included in the 2021 WHO classification of lung tumors. Case Presentation: We report a case of HLCCST of the left lower lung in a 40-year-old female who was admitted to our hospital after pulmonary nodules were discovered. A plain chest CT scan showed a nodular high-density shadow measuring approximately 8 mm in diameter in the left lower lung. The lesion had clear borders, uneven internal density, and a low-density central vacuolar area. The left lower lung was partially resected by video-assisted thoracic surgery. Post-operative histopathologic diagnosis "hemangioblastoma-like clear cell stromal tumor" of the left lower lung. Conclusion: The HLCCST is an extremely rare tumor and needs long-term follow-up after operation. Clinically, it may be easily confused with other benign and malignant tumors of the lung, and diagnosis is solely determined by histopathologic examination. This case suggests that immunohistochemical CD34 can be a strong positive marker.

4.
Front Surg ; 9: 851147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35274001

RESUMO

Background: Pulmonary metastasis of benign uterine leiomyoma and uterine endometriosis has been reported; however, pulmonary benign metastasizing uterine adenomyoma has not been reported. Herein, we report the first case of pulmonary benign metastasizing uterine adenomyoma. It is very important to differentiate from pulmonary primary synovial sarcoma; histopathology and immunohistochemistry are very helpful, molecular pathology can be used if necessary. Case Presentation: A female patient was admitted to the hospital because of pulmonary nodules. Lung computed tomography (CT) showed a nodular high density shadow in the upper lobe of the right lung, with a clear boundary and a diameter of approximately 1.2 cm. A contrast CT scan showed obvious enhancement, and no obvious lobulation or burr was found. Video-assisted thoracoscopic resection of the tumor was performed. The upper lobe nodules were completely removed. Postoperative pathological report confirmed the lesion as metastatic benign adenomyoma of the right upper lung. Conclusion: The lung is the most common organ for malignant tumor metastasis, and a few benign tumors can also develop pulmonary metastasis. Pulmonary benign metastasizing adenomyoma is extremely rare, and the prognosis is very good after surgical resection. When pulmonary CT shows a solid high-density shadow, we should consider the possibility of a metastatic benign tumor.

5.
Brain Behav ; 10(7): e01643, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32515560

RESUMO

INTRODUCTION: Few studies of the effect of cardiac abnormalities on acute intracerebral hemorrhage (ICH) outcomes have been published. We sought to determine whether the left ventricular ejection fraction (LVEF) is associated with the functional outcome and mortality of acute ICH patients. METHODS: We conducted a retrospective study on 364 acute ICH patients from January to December 2016. The primary outcome was defined by the modified Rankin Scale and mortality at 3 months. The associations between LVEF and outcome were investigated using univariable and multivariable logistic regression models. RESULTS: Depressed LVEF was significantly associated with a poor functional outcome with an odds ratio [OR] of 0.966, 95% confidence interval (CI) 0.942-0.991, p = .008, and high mortality (OR 0.968 [95% CI 0.943-0.994], p = .015) at 3 months for acute ICH patients by univariate analysis. Multivariable logistic regression analysis indicated that LVEF was an independent predictor of a poor functional outcome (OR 0.961 [95% CI 0.935-0.988], p = .005) and mortality (OR 0.949 [95% CI 0.918-0.981], p = .002). The percentage of acute ICH patients with poor functional outcome (p = .005) and mortality (p = .002) was obviously higher in the group of patients with a LVEF of <50%. CONCLUSIONS: LVEF is an independent predictor of functional outcome and mortality at 3 months for acute ICH patients. These findings could provide the evidence needed for prognosis prediction in acute ICH patients.


Assuntos
Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/fisiopatologia , Volume Sistólico , Função Ventricular Esquerda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prognóstico , Estudos Retrospectivos
6.
RSC Adv ; 10(49): 29424-29431, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35521151

RESUMO

A multiple core-shell heterostructure Rh-Rh3+ modified Ta2O5@TaON@Ta3N5 nanophotocatalyst was successfully constructed through nitriding Rh3+-doped Ta2O5 nanoparticles, which exhibited a much higher carrier separation efficiency about one order of magnitude higher than the Ta2O5@Ta3N5 precursor, and thus an excellent visible light photocatalytic H2-evolution activity (83.64 µmol g-1 h-1), much superior to that of Rh anchored Ta2O5@TaON (39.41 µmol g-1 h-1), and improved stability due to the residual Rh-O/N in the Ta3N5 shell layer. Rh-modifying significantly extended light absorption to the overall visible region. Localized built-in electric fields with hierarchical potential gradients at the multiple interfaces including a Rh/Ta3N5 Schottky junction and double n-n Ta3N5/TaON/Ta2O5 mutant heterojunctions, drove charge carriers to directionally transfer from inside to outside, and efficiently separate. Enhanced photoactivity was ascribed to a synergetic effect of improved light absorption ability, increased carrier separation efficiency, and accelerated surface reaction. A promising strategy of developing excellent Ta3N5-based photocatalysts for solar energy conversion is provided by constructing double n-n mutant heterojunctions.

7.
Neurobiol Dis ; 134: 104648, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31676238

RESUMO

Accumulation of DNA damage has been detected in the spinal cord of patients as well as in the G93A mouse model of amyotrophic lateral sclerosis (ALS). Wild-type p53-induced phosphatase 1 (Wip1) is a p53-inducible serine/threonine phosphatase that terminates DNA-damage responses via dephosphorylation of DNA-damage response proteins, namely ataxia-telangiectasia mutated (ATM) kinase, checkpoint kinase 2, and p53, thus enhancing cell proliferation. However, the role of Wip1, DNA-damage responses, and their interaction in ALS development remains to be elucidated. Here, we showed that Wip1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro. The DNA-damage response was activated in superoxide dismutase 1 (SOD1) G93A-transfected cells. However, increased expression of Wip1 improved cell viability and inhibited the DNA-damage response in mutated SOD1G93A cells. Further studies demonstrated that decreased Wip1 expression reduced cell viability and further activated the DNA-damage response in chronic H2O2-treated NSC34 cells. In contrast, Wip1 promoted cell survival and suppressed DNA damage-induced apoptosis during persistent DNA damage conditions. Over-expression of Wip1 in the central nervous system (CNS) can delay the onset of disease symptoms, extended the survival, decreased MN loss improved motor function and inhibit the DNA-damage response in SOD1 G93A mice. Furthermore, homeodomain-interacting protein kinase 2 (HIPK2) promoted the degradation of Wip1 via the ubiquitin-proteasome system during chronic stress. These findings indicate that persistent accumulation of DNA damage and subsequent chronic activation of the downstream DNA damage-response ATM and p53 pro-apoptotic signaling pathways may trigger neuronal dysfunction and neuronal death in ALS. Wip1 may play a protective role by targeting the DNA-damage response in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Dano ao DNA/fisiologia , Neurônios Motores/metabolismo , Proteína Fosfatase 2C/metabolismo , Transdução de Sinais/fisiologia , Esclerose Lateral Amiotrófica/metabolismo , Animais , Apoptose/fisiologia , Regulação para Baixo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/patologia
8.
Mol Biol Rep ; 46(6): 6299-6309, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529340

RESUMO

Abnormally protein aggregation and deposition are key pathological features of ALS, which may related with dysfunctional cellular autophagy. In the current study, we found that, compared with wtSOD1 cells, serum starvation treatment resulted in significant higher percentage of apoptosis in mutSOD1 cells; Lithium treatment exerted protection for those mutSOD1 cells, with decreased GFP-tagged mutant SOD1 protein aggregates deposition; Whereas, pre-treatment with Baf or 3-MA (autophagy inhibitors) blocked protection of lithium for mutant SOD1 cells, and induced increased GFP-tagged mutant SOD1 protein aggregation. Further, Western blots results showed that lithium treatment led to decrease of mutant hSOD1 protein levels in both Triton X-100 soluble and Triton X-100 insoluble fraction of mutSOD1 cells. Besides, improper binding of mutant SOD1 proteins' aggregates with p-CREB (Ser133) (transcription factor) in mutSOD1 cells were demonstrated; whereas lithium treatment attenuated this fault interaction. In conclusion, our results showed that, in mutSOD1 cells, mutSOD1 protein aggregates were related with abnormal autophagic regulation. Lithium treatment could induce autophagy and enhance clearance of protein aggregates, further exerting protection on mutSOD1 cells. More importantly, we uncovered another distinct pathological role of mutSOD1 protein aggregates, that is abnormal binding with p-CREB (Ser133), an important transcription factor, which may play crucial role in the PI3K-Akt-CREB-AEG-1 signaling pathway.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Lítio/farmacologia , Mutação , Neurônios/citologia , Superóxido Dismutase-1/metabolismo , Animais , Autofagia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação , Dobramento de Proteína/efeitos dos fármacos , Transdução de Sinais , Superóxido Dismutase-1/química , Superóxido Dismutase-1/genética , Transfecção
9.
Brain Res Bull ; 146: 287-301, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30690059

RESUMO

Oxidative stress has been considered as a principal mechanism of motor neuron death in amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease which could be caused by dominant mutations in an antioxidant enzyme superoxide dismutase-1 (SOD1). The aim of the present study was to investigate the potential neuroprotective effects and mechanisms of urate, an important endogenous antioxidant and a biomarker of favorable ALS progression rates, in the mutant human SOD1-related cellular and Drosophila models of ALS. Our results showed that urate treatment provided neuroprotective effects as confirmed by enhanced survival, attenuated motor impairments, reduced oxidative damage and increased antioxidant defense in hSOD1-G85R-expressing Drosophila models of ALS. In vitro studies, we demonstrated that urate protected motor neurons (NSC-34 cells) against hSOD1-G93A-induced cell damage and apoptosis by decreasing reactive oxygen specials (ROS) production and oxidative damage. Moreover, urate markedly increased the expression and activation of nuclear factor erythroid 2-related factor 2 (Nrf2), stimulated Nrf2-targeted antioxidant gene glutathione cysteine ligase catalytic subunit (GCLC) expression and glutathione (GSH) synthesis by upregulating Akt/GSK3ß pathway. Furthermore, the inhibition of Akt pathway with LY294002 abolished urate-mediated elevation of GSH synthesis and neuroprotective effects both in vivo and in vitro. Overall, these results suggested that, in addition to its direct scavenging of ROS, urate markedly enhanced GSH expression by activating Akt/GSK3ß/Nrf2/GCLC pathway, and thus offering neuroprotective effects on motor neurons against oxidative stress.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Glutationa/metabolismo , Ácido Úrico/farmacologia , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Glutationa/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Camundongos , Neurônios Motores/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Ácido Úrico/metabolismo
10.
DNA Repair (Amst) ; 74: 51-62, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30630676

RESUMO

Increasing evidence indicates that DNA damage and p53 activation play major roles in the pathological process of motor neuron death in amyotrophic lateral sclerosis (ALS). Human SpeedyA1 (Spy1), a member of the Speedy/Ringo family, enhances cell proliferation and promotes tumorigenesis. Further studies have demonstrated that Spy1 promotes cell survival and inhibits DNA damage-induced apoptosis. We showed that the Spy1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro by qRT-PCR, western blotting, and Immunoassay tests. In addition, we established that over-expression of human SOD1 mutant G93A led to a decreased expression of Spy1. Furthermore, DNA damage response was activated in SOD1G93A-transfected cells (mSOD1 cells). Moreover, decreased Spy1 expression reduced cell viability and further activated the DNA damage response in mSOD1 cells. In contrast, increased Spy1 expression improved cell viability and inhibited the DNA damage response in mSOD1 cells. These results suggest that Spy1 plays a protective role in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS as well as for trial designs, such as investigating the role of oncogenic proteins in ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA/genética , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Mutação , Superóxido Dismutase-1/genética , Animais , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Linhagem Celular , Sobrevivência Celular , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos
11.
ACS Appl Mater Interfaces ; 10(34): 28936-28947, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30068077

RESUMO

On the basis of high stability of phosphorus-oxygen linkage, we constructed two microporous covalent phosphazene-based frameworks (CPFs), for the first time, by choosing hexachlorocyclotriphosphazene as a core unit and polyhydroxy aromatic compounds (hydroquinone or phloroglucinol) as monomers, named CPF-D and CPF-T, respectively. Characterization studies by using Fourier transform infrared, nuclear magnetic resonance, thermal gravimetric analysis, 60Co γ-ray irradiation, and so forth, demonstrated that both of the CPF materials have excellent acid and radiation stability and relatively higher thermal stability. The results of batch adsorption experiments show that CPF-T is significantly more capable of sorbing uranium than CPF-D. In a pure uranium system with higher acidity (pH 1), the uranium sorption amount of CPF-T can reach up to 140 mg g-1. Distinctively, in mixed-metal solution with 12 coexisting cations, CPF-T shows relatively stable and excellent uranium adsorption capability over a wide range of acidity (pH 4 to 3 M HNO3), and the difference in uranium sorption amounts is less than 30% with the maximum of 0.26 mmol g-1 at pH 4 and the minimum of 0.20 mmol g-1 at 3 M HNO3, which is far superior to that of the conventional solid-phase extractant (SPE) materials previously reported. The research results suggested that the sorption model based on the speculated mechanism of size-matching plus hydrogen bond network has played a dominant role in the process of uranium adsorption. The proposed strategy for the one-pot fabrication of an acid-resistant microporous framework materials by bridging the aromatic monomers via P-O bonds provides an alternative approach for the design and synthesis of new SPE materials with size-matching function desired for effective separation of uranium or other valuable metals from highly acidic environments.

12.
Mol Cell Neurosci ; 90: 1-11, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29777762

RESUMO

AEG-1 has received extensive attention on cancer research. However, little is known about its roles in astrogliosis of Amyotrophic lateral sclerosis (ALS). In this study, we detected AEG-1 expression in hSOD1G93A-positive (mut-SOD1) astrocytes and wild type (wt-SOD1) astrocytes, and intend to elucidate its potential functions in ALS related astrogliosis and the always accompanied dysregulated glutamate clearance. Results showed elevated protein and mRNA levels of AEG-1 in mut-SOD1 astrocytes; Also, NF-κB signaling pathway related proteins and inflammatory cytokines were upregulated in mut-SOD1 astrocytes; AEG-1 knockdown attenuated astrocytes proliferation and pro-inflammatory release; also we found that AEG-1 silence inhibited translocation of p65 from cytoplasma to nuclear, which was associated with inhibited NF-κB signaling. Besides, excitatory amino acid transporter-2 (EAAT2) expression levels were significantly decreased, accompanied by impaired glutamate clearance ability, in mut-SOD1 astrocytes; yin yang 1 (YY1), a transcriptional inhibitor for EAAT2, increased in nucleus of mut-SOD1 astrocytes. AEG-1 silence inhibited translocation of YY1 to nucleus, increased EAAT2 expression levels, and enhanced astrocytic ability of glutamate clearance, ultimately exerted the neuronal protection. Findings from this study implicate potential function of AEG-1 in mut-SOD1 related astrogliosis and the accompanied excitatory cytotoxic mechanism in ALS.

13.
Brain Res Bull ; 140: 299-310, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29842900

RESUMO

Amyotrophic lateral sclerosis (ALS) is a degenerative disease with a progressive loss of motor neurons in the central nervous system (CNS). However, there are unsolved problems with the therapies for this disease. α-Lipoic acid (LA) is a natural, universal antioxidant capable of scavenging hydroxyl radicals as well as regenerating a series of antioxidant enzymes that has been widely used in clinical settings. This study aimed to evaluate the antioxidant and neuroprotective effects of LA in ALS cell and Drosophila models with mutant G85R and G93A hSOD1 genes. The biological effects of LA and the protein levels of several antioxidant factors were examined, as were those of phospho-Akt and phospho-ERK. Furthermore, specific inhibitors of the PI3K/Akt and MEK/ERK signaling pathways were used to analyze their effects on LA-induced antioxidant expression in vivo and in vitro. Evidences showed that the mutant hSOD1 resulted in the increased oxidative stress, abnormal antioxidant signaling and pathological behaviors in motor performance and survival compared with non-mutant hSOD1 models, treatment with LA improved motor activity and survival in transgenic flies, prevented NSC34 cells from mutant hSOD1 or H2O2 induced decreased antioxidant enzymes as well as increased ROS levels. In addition, LA regulated the expression levels of antioxidant proteins in a dose- and periodical time-dependent manner, which might be mediated by ERK/Akt pathway activation and independent from the mutant hSOD1 gene. Our observations suggest that LA exerts strong and positive antioxidant and neuroprotective effects through the activation of the ERK-Akt pathway in hSOD1 ALS models.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ácido Tióctico/farmacologia , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Linhagem Celular , Modelos Animais de Doenças , Drosophila melanogaster , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
14.
Rev Sci Instrum ; 88(6): 065106, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28667970

RESUMO

The radiographic testing (RT) image of a steam turbine manufacturing enterprise has the characteristics of low gray level, low contrast, and blurriness, which lead to a substandard image quality. Moreover, it is not conducive for human eyes to detect and evaluate defects. This study proposes an adaptive pseudo-color enhancement method for weld radiographic images based on the hue, saturation, and intensity (HSI) color space and the self-transformation of pixels to solve these problems. First, the pixel's self-transformation is performed to the pixel value of the original RT image. The function value after the pixel's self-transformation is assigned to the HSI components in the HSI color space. Thereafter, the average intensity of the enhanced image is adaptively adjusted to 0.5 according to the intensity of the original image. Moreover, the hue range and interval can be adjusted according to personal habits. Finally, the HSI components after the adaptive adjustment can be transformed to display in the red, green, and blue color space. Numerous weld radiographic images from a steam turbine manufacturing enterprise are used to validate the proposed method. The experimental results show that the proposed pseudo-color enhancement method can improve image definition and make the target and background areas distinct in weld radiographic images. The enhanced images will be more conducive for defect recognition. Moreover, the image enhanced using the proposed method conforms to the human eye visual properties, and the effectiveness of defect recognition and evaluation can be ensured.

15.
Int J Mol Sci ; 17(12)2016 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-27999308

RESUMO

BACKGROUND: Mutations in the Cu/Zn superoxide dismutase (SOD1) gene have been linked to amyotrophic lateral sclerosis (ALS). However, the molecular mechanisms have not been elucidated yet. Homer family protein Homer1b/c is expressed widely in the central nervous system and plays important roles in neurological diseases. In this study, we explored whether Homer1b/c was involved in SOD1 mutation-linked ALS. RESULTS: In vitro studies showed that the SOD1 G93A mutation induced an increase of Homer1b/c expression at both the mRNA and protein levels in NSC34 cells. Knockdown of Homer1b/c expression using its short interfering RNA (siRNA) (si-Homer1) protected SOD1 G93A NSC34 cells from apoptosis. The expressions of Homer1b/c and apoptosis-related protein Bax were also suppressed, while Bcl-2 was increased by lithium and valproic acid (VPA) in SOD1 G93A NSC34 cells. In vivo, both the mRNA and protein levels of Homer1b/c were increased significantly in the lumbar spinal cord in SOD1 G93A transgenic mice compared with wild type (WT) mice. Moreover, lithium and VPA treatment suppressed the expression of Homer1b/c in SOD1 G93A mice. CONCLUSION: The suppression of SOD1 G93A mutation-induced Homer1b/c upregulation protected ALS against neuronal apoptosis, which is a novel mechanism of the neuroprotective effect of lithium and VPA. This study provides new insights into pathogenesis and treatment of ALS.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Proteínas de Arcabouço Homer/biossíntese , Lítio/uso terapêutico , Superóxido Dismutase/genética , Ácido Valproico/uso terapêutico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Apoptose/genética , Linhagem Celular , Predisposição Genética para Doença , Proteínas de Arcabouço Homer/antagonistas & inibidores , Proteínas de Arcabouço Homer/genética , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética
16.
Sci Rep ; 6: 26120, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27212435

RESUMO

Amyotrophic lateral sclerosis (ALS) is an incurable neurological degenerative disease. It can cause irreversible neurological damage to motor neurons; typical symptoms include muscle weakness and atrophy, bulbar paralysis and pyramidal tract signs. The ALS-mimicking disease cervical spondylotic myelopathy (CSM) presents similar symptoms, but analysis of breath volatile organic compounds (VOCs) can potentially be used to distinguish ALS from CSM. In this study, breath samples were collected from 28 ALS and 13 CSM patients. Subsequently, gas chromatography/mass spectrometry (GCMS) was used to analyze breath VOCs. Principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLSDA) were the statistical methods used to process the final data. We identified 4 compounds with significantly decreased levels in ALS patients compared with CSM controls: (1) carbamic acid, monoammonium salt; (2) 1-alanine ethylamide, (S)-; (3) guanidine, N,N-dimethyl-; and (4) phosphonic acid, (p-hydroxyphenyl)-. Currently, the metabolic origin of the VOCs remains unclear; however, several pathways might explain the decreasing trends observed. The results of this study demonstrate that there are specific VOC profiles associated with ALS and CSM patients that can be used to differentiate between the two. In addition, these metabolites could contribute to a better understanding of the underlying pathophysiological mechanisms of ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Testes Respiratórios/métodos , Compressão da Medula Espinal/diagnóstico , Espondilose/complicações , Compostos Orgânicos Voláteis/análise , Esclerose Lateral Amiotrófica/patologia , Bioestatística , Diagnóstico Diferencial , Expiração , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Compressão da Medula Espinal/patologia
17.
Rev Sci Instrum ; 87(3): 035110, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27036822

RESUMO

Improving the efficiency and accuracy of weld defect classification is an important technical problem in developing the radiographic testing system. This paper proposes a novel weld defect classification method based on information fusion technology, Dempster-Shafer evidence theory. First, to characterize weld defects and improve the accuracy of their classification, 11 weld defect features were defined based on the sub-pixel level edges of radiographic images, four of which are presented for the first time in this paper. Second, we applied information fusion technology to combine different features for weld defect classification, including a mass function defined based on the weld defect feature information and the quartile-method-based calculation of standard weld defect class which is to solve a sample problem involving a limited number of training samples. A steam turbine weld defect classification case study is also presented herein to illustrate our technique. The results show that the proposed method can increase the correct classification rate with limited training samples and address the uncertainties associated with weld defect classification.

19.
Front Aging Neurosci ; 7: 204, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26539112

RESUMO

Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease causing death of motor neurons. This study investigated the roles of energy metabolism in the pathogenesis of ALS in the SOD1(G93A) transgenic mouse model. Control and SOD1(G93A) mice were administered with shcontrol or shPGC-1α in combination with PBS or thiazolidinedione (TZD) for 8 weeks. Gene expression was analyzed by quantitative real-time PCR and Western blot. ROS and fibrosis were assessed with a colorimetric kit and Sirius staining, respectively. Inflammatory cytokines were measured using ELISA kits. The levels of tissue ROS and serum inflammatory cytokines were significantly higher in SOD1(G93A) mice compared to control mice, and knocking down peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) drastically increased cytokine levels in both control and SOD1(G93A) mice. Muscle fibrosis was much severer in SOD1(G93A) mice, and worsened by silencing PGC-1α and attenuated by TZD. The expression levels of PGC-1α, SOD1, UCP2, and cytochrome C were substantially reduced by shPGC-1α and increased by TZD in muscle of both control and SOD1(G93A) mice, whereas the level of NF-κB was significantly elevated in SOD1(G93A) mice, which was further increased by PGC-1α silencing. These data indicated that disruption of energy homeostasis would exacerbate the pathological changes caused by SOD1 mutations to promote the pathogenesis of ALS.

20.
Mol Cell Neurosci ; 68: 303-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26320681

RESUMO

Astrocyte elevated gene-1 (AEG-1) has been reported to regulate the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and is also regulated by it. This study investigated how AEG-1 participates in the survival pathway of motor neurons in amyotrophic lateral sclerosis (ALS). We found reduced levels of AEG-1 in ALS motor neurons, both in vivo and in vitro, compared to wild type controls. Moreover, AEG-1 silencing demonstrated inhibition of the PI3K/Akt pathway and increased cell apoptosis. Additionally, the PI3K/Akt pathway in mSOD1 cells was unresponsive under serum deprivation conditions compared to wtSOD1 cells. These results suggest that AEG-1 deficiency, together with the inhibited PI3K/Akt pathway was associated with decreased viability of ALS motor neurons. However, the mRNA levels of AEG-1 were still lower in mSOD1 cells compared to the control groups, though the signaling pathway was activated by application of a PI3-K activator. This suggests that in ALS motor neurons, some unknown interruption exists in the PI3K/Akt/CREB/AEG-1 feedback loop, thus attenuating the protection by this signaling pathway. Together, these findings support that AEG-1 is a critical factor for cell survival, and the disrupted PI3K/Akt/CREB/AEG-1cycle is involved in the death of injured motor neurons and pathogenesis of ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Proteínas de Membrana/metabolismo , Neurônios Motores/patologia , Transdução de Sinais/fisiologia , Esclerose Lateral Amiotrófica/genética , Animais , Apoptose/genética , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Embrião de Mamíferos , Feminino , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios Motores/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA/fisiologia , RNA Interferente Pequeno/farmacologia , Proteínas de Ligação a RNA , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/patologia , Superóxido Dismutase/genética
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