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1.
Sensors (Basel) ; 21(3)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498424

RESUMEN

Flame monitoring of industrial combustors with high-reliability sensors is essential to operation security and performance. An ion current flame sensor with a simple structure has great potential to be widely used, but a weak ion current is the critical defect to its reliability. In this study, parameters of the ion current sensor used for monitoring flames on a Bunsen burner are suggested, and a method of further improving the ion current is proposed. Effects of the parameters, including the excitation voltage, electrode area, and electrode radial and vertical positions on the ion current, were investigated. The ion current grew linearly with the excitation voltage. Given that the electrodes were in contact with the flame fronts, the ion current increased with the contact area of the cathode but independent of the contact area of the anode. The smaller electrode radial position resulted in a higher ion current. The ion current was insensitive to the anode vertical position but largely sensitive to the cathode vertical position. Based on the above ion current regularities, the sensor parameters were suggested as follows: The burner served as a cathode and the platinum wire acted as an anode. The excitation voltage, anode radial and vertical positions were 120 V, 0 mm, and 6 mm, respectively. The method of further improving the ion current by adding multiple sheet cathodes near the burner exit was proposed and verified. The results show that the ion current sensor with the suggested parameters could correctly identify the flame state, including the ignition, combustion, and extinction, and the proposed method could significantly improve the magnitude of the ion current.

2.
J Ovarian Res ; 17(1): 38, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347589

RESUMEN

PCOS is a widespread disease that primarily caused in-pregnancy in pregnant-age women. Normoandrogen (NA) and Hyperandrogen (HA) PCOS are distinct subtypes of PCOS, while bio-markers and expression patterns for NA PCOS and HA PCOS have not been disclosed. We performed microarray analysis on granusola cells from NA PCOS, HA PCOS and normal tissue from 12 individuals. Afterwards, microarray data were processed and specific genes for NA PCOS and HA PCOS were identified. Further functional analysis selected IL6R and CD274 as new NA PCOS functional markers, and meanwhile selected CASR as new HA PCOS functional marker. IL6R, CD274 and CASR were afterwards experimentally validated on mRNA and protein level. Subsequent causal relationship analysis based on Apriori Rules Algorithm and co-occurrence methods identified classification markers for NA PCOS and HA PCOS. According to classification markers, downloaded transcriptome datasets were merged with our microarray data. Based on merged data, causal knowledge graph was constructed for NA PCOS or HA PCOS and female infertility on NA PCOS and HA PCOS. Gene-drug interaction analysis was then performed and drugs for HA PCOS and NA PCOS were predicted. Our work was among the first to indicate the NA PCOS and HA PCOS functional and classification markers and using markers to construct knowledge graphs and afterwards predict drugs for NA PCOS and HA PCOS based on transcriptome data. Thus, our study possessed biological and clinical value on further understanding the inner mechanism on the difference between NA PCOS and HA PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico , Embarazo , Femenino , Humanos , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Transcriptoma , Reconocimiento de Normas Patrones Automatizadas , Células de la Granulosa/metabolismo
3.
EMBO Mol Med ; 16(1): 10-39, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38177530

RESUMEN

Endocrine resistance is a crucial challenge in estrogen receptor alpha (ERα)-positive breast cancer (BCa). Aberrant alteration in modulation of E2/ERα signaling pathway has emerged as the putative contributor for endocrine resistance in BCa. Herein, we demonstrate that MYSM1 as a deubiquitinase participates in modulating ERα action via histone and non-histone deubiquitination. MYSM1 is involved in maintenance of ERα stability via ERα deubiquitination. MYSM1 regulates relevant histone modifications on cis regulatory elements of ERα-regulated genes, facilitating chromatin decondensation. MYSM1 is highly expressed in clinical BCa samples. MYSM1 depletion attenuates BCa-derived cell growth in xenograft models and increases the sensitivity of antiestrogen agents in BCa cells. A virtual screen shows that the small molecule Imatinib could potentially interact with catalytic MPN domain of MYSM1 to inhibit BCa cell growth via MYSM1-ERα axis. These findings clarify the molecular mechanism of MYSM1 as an epigenetic modifier in regulation of ERα action and provide a potential therapeutic target for endocrine resistance in BCa.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/genética , Moduladores de los Receptores de Estrógeno/farmacología , Moduladores de los Receptores de Estrógeno/uso terapéutico , Histonas/metabolismo , Proliferación Celular , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Transactivadores/metabolismo , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo
4.
Front Pharmacol ; 13: 946811, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36188615

RESUMEN

Dysregulated epigenetic enzymes and resultant abnormal epigenetic modifications (EMs) have been suggested to be closely related to tumor occurrence and progression. Histone modifications (HMs) can assist in maintaining genome stability, DNA repair, transcription, and chromatin modulation within breast cancer (BC) cells. In addition, HMs are reversible, dynamic processes involving the associations of different enzymes with molecular compounds. Abnormal HMs (e.g. histone methylation and histone acetylation) have been identified to be tightly related to BC occurrence and development, even though their underlying mechanisms remain largely unclear. EMs are reversible, and as a result, epigenetic enzymes have aroused wide attention as anti-tumor therapeutic targets. At present, treatments to restore aberrant EMs within BC cells have entered preclinical or clinical trials. In addition, no existing studies have comprehensively analyzed aberrant HMs within BC cells; in addition, HM-targeting BC treatments remain to be further investigated. Histone and non-histone protein methylation is becoming an attractive anti-tumor epigenetic therapeutic target; such methylation-related enzyme inhibitors are under development at present. Consequently, the present work focuses on summarizing relevant studies on HMs related to BC and the possible mechanisms associated with abnormal HMs. Additionally, we also aim to analyze existing therapeutic agents together with those drugs approved and tested through pre-clinical and clinical trials, to assess their roles in HMs. Moreover, epi-drugs that target HMT inhibitors and HDAC inhibitors should be tested in preclinical and clinical studies for the treatment of BC. Epi-drugs that target histone methylation (HMT inhibitors) and histone acetylation (HDAC inhibitors) have now entered clinical trials or are approved by the US Food and Drug Administration (FDA). Therefore, the review covers the difficulties in applying HM-targeting treatments in clinics and proposes feasible approaches for overcoming such difficulties and promoting their use in treating BC cases.

5.
Materials (Basel) ; 15(24)2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36556558

RESUMEN

Improving the toughness of diamond composites has become an industrial demand. In this work, Co50Ni40Fe10 multi-element alloy was designed as binder for diamond-based composites prepared by high temperature and high pressure (HTHP). Two methods of mixing-sintering and infiltration-sintering were used to prepare diamond-based composites with different diamond contents. The phase diagrams of Co-C and Co50Ni40Fe10-C at 6 GPa were calculated by Thermo-Calc. The results show that Co50Ni40Fe10 multi-element alloy promotes the sintering of diamond powder than element Co. The transverse rupture strength (TRS) of sintered diamond with Co50Ni40Fe10 (Co50Ni40Fe10-75 vol% diamond) is higher than that of Co-Comp (Co-75 vol% diamond). The TRS of polycrystalline diamond (PCD) with Co50Ni40Fe10 alloy binder is up to 1360.3 MPa, which is 19.2% higher than Co-PCD. Compared with Co, using Co50Ni40Fe10 as binder results in a less metal residue in PCD, while the metal cluster area is smaller and the metal distribution is more uniform.

6.
J Colloid Interface Sci ; 582(Pt B): 447-458, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32896674

RESUMEN

In this paper, we designed and prepared a novel metal organic framework (MOF)/holey graphene (HG) composites as electrode materials for electrochemistry and capacitive deionization (CDI). The MOF nanoparticles were attached to the surface of the HG sheets to form layered porous structure, which promoted the transport of ions and electrons in the electrode/electrolyte interfaces. Additionally, the synergistic effect of these composite electrodes, which combined pseudocapacitance performance of MOF and the high conductivity of graphene, contributed to enhancing the performance of electrochemistry and CDI. The MOF/HG-2 exhibited high capacitances of 526 F g-1 at current rates of 0.1 A g-1, low charge transfer resistance of 0.53 Ω, and excellent cycling stability (retention of about 90.3% after 5000 cycles at 2 A g-1). As electrode materials for CDI, the MOF/HG-2 displayed a remarkable electrosorption capacity of 39.6 mg g-1 with initial salt concentration of 800 mg L-1, and there was no obvious attenuation after 20 CDI regeneration cycles. These results confirmed that MOF/HG was a promising electrode material for the actual application of CDI.

7.
Bioresour Bioprocess ; 8(1): 102, 2021 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-38650272

RESUMEN

ß-1,3-glucanase can specifically hydrolyze glucans to oligosaccharides and has potential applications in biotechnology. We used the metatranscriptomic technology to discover a thermophilic ß-1,3-glucanase from compost. The phylogenetic study shows that it belongs to the family 16 glycoside hydrolase (GH16) and is most homologous with an enzyme from Streptomyces sioyaensis, an actinobacterium. It has the activity of 146.9 U/mg in the optimal reaction condition (75 °C and pH 5.5). Its catalytic domain was crystallized and diffracted to 1.14 Å resolution. The crystal structure shows a sandwich-like ß-jelly-roll fold with two disulfide bonds. After analyzing the occurring frequencies of these cysteine residues, we designed two mutants (C160G and C180I) to study the role of these disulfide bonds. Both mutants have decreased their optimal temperature from 75 to 70 °C, which indicate that the disulfide bonds are important to maintain thermostability. Interestingly, the activity of C160G has increased ~ 17% to reach 171.4 U/mg. We speculate that the increased activity of C160G mutant is due to increased dynamics near the active site. Our studies give a good example of balancing the rigidity and flexibility for enzyme activity, which is helpful for protein engineering.

8.
PLoS One ; 13(11): e0205958, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30403681

RESUMEN

It is generally difficult to predict fractures of low-permeability reservoirs under high confining pressures by data statistical method and simplified strain energy density method. In order to establish a series of geomechanical models for the prediction of multi-scale fractures in brittle tight sandstones, firstly, through a series of rock mechanics experiments and CT scanning, we determined 0.85 σc as the key thresholds for mass release of elastic strain energy and bursting of micro-fractures. A correlation between fracture volume density and strain energy density under uniaxial stress state was developed based on the Theory of Geomechanics. Then using the combined Mohr-Coulomb criterion and Griffith's criterion and considering the effect of filling degree in fractures, we continued to modify and deduce the mechanical models of fracture parameters under complex stress states. Finally, all the geomechanical equations were loaded into the finite element (FE) platform to quantitatively simulate the present-day 3-D distributions of fracture density, aperture, porosity, permeability and occurrence based on paleostructure restoration of the Keshen anticline. Its predictions agreed well with in-situ core observations and formation micro-imaging (FMI) interpretations. The prediction results of permeability were basically consistent with the unobstructed flow distributions before and after the reservoir reformation.


Asunto(s)
Fenómenos Geológicos , Modelos Teóricos , Estrés Mecánico , Análisis de Elementos Finitos , Sedimentos Geológicos/análisis , Tomografía Computarizada por Rayos X
9.
Clin Cardiol ; 29(1): 13-7, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16477772

RESUMEN

BACKGROUND: Terrorism, such as the attacks on the World Trade Center (WTC) on September 11, 2001, result in higher stress-related disorders, especially in those persons in close proximity. HYPOTHESIS: Cardiac events resulting from the September 11, 2001 tragedy have not been detailed near the WTC. METHODS: Patients admitted to the Telemetry and Coronary Care Units at New York Methodist Hospital 4 miles from the WTC 60 days prior to and after the September 11 attacks were analyzed. In all, 1,653 admissions were reviewed: 427 records pre 9/11/2001 and 422, 393, and 411 records in the post-9/11/2001, pre-9/11/2000, and post-9/11/2000 data sets, respectively. Patients were categorized based on diagnosis: acute myocardial infarction (MI), unstable angina (UA), tachyarrhythmia (TA), and others (including syncope and congestive heart failure). RESULTS: There was a significant difference in the proportion of the various cardiac diagnoses post 9/11/01 (p = 0.008 by chi-square analysis). Compared with pre 9/11/2001, there were significantly more patients with acute MI (15.5 vs. 11.2%) and TA (19.9 vs. 13.6%) but fewer with UA (39.6 vs. 47.3%) after the terrorist attacks. The distribution of cardiac events during a similar period of time in 2000 revealed no such pattern. CONCLUSIONS: There was a significant increase in acute MI and TA and a smaller increase in UA after the September 11 attacks. The difference did not appear to be due to temporal variation. It appears that stress likely contributed to an increase in TA by itself or with ischemia, resulting in progression of UA to acute MI.


Asunto(s)
Cardiopatías/epidemiología , Ataques Terroristas del 11 de Septiembre , Trastornos por Estrés Postraumático/epidemiología , Anciano , Femenino , Humanos , Masculino , Ciudad de Nueva York/epidemiología , Admisión del Paciente/estadística & datos numéricos
10.
Huan Jing Ke Xue ; 33(1): 239-46, 2012 Jan.
Artículo en Zh | MEDLINE | ID: mdl-22452217

RESUMEN

Three environmental endocrine disrupting chemicals (EDCs), named nonylphenol (NP), octylphenol (4-t-OP) and bisphenol A (BPA), in sediments of the Suzhou Creek and its branches were detected using gas chromatography-mass spectrometry (GC-MS) method. The results showed that the concentration of three chemicals varied greatly from site to site, which ranged from < 1.0-5 800, < 0.10-39 and 0.90-180 microg x kg(-1), respectively. In general, the accumulation of pollutants in sediments closely related to the intensity of anthropogenic activities: the concentration of three chemicals in sediments of municipal section of the creek are significantly higher than those in the sections of suburb of Shanghai city and Jiangsu province; the chemical concentrations in sediments of branches are significantly higher than those of the main stream of the creek. Significant correlations between each two of the three chemicals in sediments were observed, implying their similar source provenance. Taking nonylphenol as an example, the environmental risks of the EDCs in sediments were assessed. The result indicated that this chemical in the entire creek except the Wujiagang Bridge point had posed potential toxic risks to ecological system. Therefore, more countermeasures should be taken to prevent EDCs from entering the creek.


Asunto(s)
Disruptores Endocrinos/análisis , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Compuestos de Bencidrilo/análisis , China , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas/métodos , Fenoles/análisis , Medición de Riesgo , Ríos
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