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1.
Nature ; 621(7979): 483-486, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37674076

RESUMEN

Magnetic fields are fundamental to the evolution of galaxies, playing a key role in the astrophysics of the interstellar medium and star formation. Large-scale ordered magnetic fields have been mapped in the Milky Way and nearby galaxies1,2, but it is not known how early in the Universe such structures formed3. Here we report the detection of linearly polarized thermal emission from dust grains in a strongly lensed, intrinsically luminous galaxy that is forming stars at a rate more than 1,000 times that of the Milky Way at redshift 2.6, within 2.5 Gyr of the Big Bang4,5. The polarized emission arises from the alignment of dust grains with the local magnetic field6,7. The median polarization fraction is of the order of 1%, similar to nearby spiral galaxies8. Our observations support the presence of a 5-kiloparsec-scale ordered magnetic field with a strength of around 500 µG or lower, oriented parallel to the molecular gas disk. This confirms that such structures can be rapidly formed in galaxies, early in cosmic history.

2.
ScientificWorldJournal ; 2014: 821025, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25258737

RESUMEN

Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology and its application are analyzed for paste backfill mining in Daizhuang Coal Mine; a practical implementation shows that paste backfill mining can improve the safety and excavation rate of coal mining, which can effectively resolve surface subsidence problems caused by underground mining activities, by utilizing solid waste such as coal gangues as a resource. Therefore, paste backfill mining is an effective clean coal mining technology, which has widespread application.


Asunto(s)
Minas de Carbón/métodos , Carbón Mineral/análisis , Contaminación Ambiental/análisis , Contaminación Ambiental/prevención & control , China , Salud Ambiental/métodos , Geografía , Humanos , Reproducibilidad de los Resultados , Administración de la Seguridad/métodos
3.
Zhonghua Yi Xue Za Zhi ; 94(36): 2841-3, 2014 Sep 30.
Artículo en Zh | MEDLINE | ID: mdl-25534103

RESUMEN

OBJECTIVE: To analyze the clinical characteristics, treatment and prognosis of hemophagocytic lymphohistiocytosis (HLH) patients with Epstein-Barr viremia (EBV). METHODS: A retrospective study was conducted to analyze the clinical data of 80 HLH patients aged ≥ 14 years with EBV-DNA >1 000 copies/ml in peripheral blood from 2008 to 2013. RESULTS: There were EBV-HLH (n = 46), HLH-associated lymphoma (n = 30) and primary HLH (n = 4). Among the relevant laboratory parameters, inter-group statistical differences existed only in alanine transaminase (ALT) and aspartate aminotransferase (AST) (P = 0.021, 0.035). The median follow-up period was 2.0 (0.5-20.0) months. And the 1-month, 3-month, 6-month and 12-month overall survival rates were 58.8%, 37.5%, 29.7% and 19.6% respectively. CONCLUSIONS: HLH patients with EBV have a pernicious clinical course with a poor prognosis. And it makes little sense for distinguishing HLH-associated lymphoma from EBV-HLH through routine laboratory tests.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Linfohistiocitosis Hemofagocítica , Viremia , Humanos , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
4.
Materials (Basel) ; 16(15)2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-37570065

RESUMEN

The grout annulus (GA) has a significant effect on the tensile performance of rockbolts in mining engineering. However, little research has been conducted to use modified cable elements to study this effect quantitatively. This paper used the modified cable elements in FLAC3D to study the effect of the GA on the tensile performance of rockbolts. The two-stage coupling law was used to simulate the behaviour of the GA. The stress had a linear relation with the slippage before the shear strength (SS). After the SS, the stress decreased exponentially. Numerical in situ roadway reinforcement cases were used to study the influence of the grout annulus on the tensile performance of rockbolts. The results showed that, when the SS of the GA increased from 3.2 MPa to 6.4 Mpa, the peak force of rockbolts increased from 247 kN to 425 kN. Moreover, when the SS of the GA increased from 3.2 Mpa to 6.4 Mpa, the distance between the position of the maximum tensile capacity and the external end decreased from 1.17 m to 0.81 m. Last, for the circular roadway, the peak force in rockbolts installed in the lateral side was 171.7 kN, which was significantly larger than the top side of 72.3 kN.

5.
Sci Rep ; 12(1): 14847, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050402

RESUMEN

Characterizing the permeability evolution and methane release is of great significance for the safe mining of the high gas outburst seams, as well as coal and gas simultaneous extraction. It contributes to reduce methane emissions from coal mining for greenhouse effect control. Theoretical analysis, laboratory testing, and numerical simulation are widely used methods to characterize the permeability and methane release with the treatment process of pressure-relief mining. However, these methods cannot fully reflect the complexity of filed practice. In this study, we report the effectiveness of protective coal seam (PCS) mining and the pressure-relief area in the protected coal seam (PDCS) based on detailed and integrated field measurements in a Chinese coal mine. To the best of our knowledge, it is the first time to measure the permeability coefficient and gas pressure evolution in the PDCS during the process of PCS longwall mining. The evolution of the permeability coefficient in the pressure-relief area during PCS mining can be divided into four stages: slowly decreasing, sharply increasing, gradually decreasing, and basically stable. The maximum permeability coefficient is 322 times of the initial value and stabilized at 100 times after the goaf compacted. The gas pressure evolution in the PDCS indicates that the strike pressure relief angle is 52.2° at the active longwall face zone, and 59.3° at the installation roadway side. The inclined pressure relief angles at the lower and upper sides of the longwall face are 75° and 78.9°, respectively. The residual gas content and gas pressure of the PDCS in the pressure-relief area are reduced to less than 6 m3/t and within 0.4 MPa, respectively. The field measurements further prove that pressure-relief mining can prevent coal and gas outbursts in PDCSs. The field observations in this paper can serve as benchmark evidence for theoretical analysis and numerical simulations, and also provide insights into realizing safety mining in similar conditions.

6.
Exp Ther Med ; 14(2): 1253-1259, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28810585

RESUMEN

Hsp70 regulates α-Synuclein (α-Syn) degeneration in Parkinson's disease (PD), indicating that Hsp70 promotion may be able to prevent or reverse α-Syn-induced toxicity in PD. Additionally, it has been demonstrated that glutamine (Gln) enhances Hsp70 expression. In the present study, Gln-induced Hsp70 promotion in pheochromocytoma was investigated with reverse transcription- quantitative polymerase chain reaction and western blotting methods. Then it was observed whether heat shock factor (HSF)-1 was required for this phenomenon with an RNA interference strategy. The regulatory role of Gln on α-Syn degeneration was also determined in the α-Syn-overexpressed PC12 [PC12 (α-Syn+)] cells, which were treated with or without the proteasomal inhibitor lactacystin (Lac). The results demonstrated that treatment with ≥10 mM Gln significantly increased Hsp70 mRNA and protein levels (P<0.05) and that this promotion was HSF-1-dependent, as HSF-1 knockout with HSF-1-specific small interfering RNA abrogated Hsp70 promotion in PC12 (α-Syn+) cells. Furthermore, Gln treatment markedly upregulated α-Syn degeneration in PC12 (α-Syn+) cells, which was significantly reduced (P<0.05) in the presence of Lac. Therefore, the present study suggests that Gln is able to induce the promotion of Hsp70 expression in PC12 cells in an HSF-1-dependent manner and that Gln-mediated Hsp70 promotion may increase α-Syn degradation even in the presence of proteasomal inhibitor. Thus, glutamine may be a potential therapeutic agent to prevent α-Syn aggregation in PD.

7.
Int J Hematol ; 105(6): 828-834, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28185204

RESUMEN

Low or absent natural killer (NK) cell activity is included as one of the HLH-2004 diagnostic criteria. To improve the diagnosis of HLH, we aimed to establish a rapid and reliable NK cell activity assay that avoids the use of radioactivity. The K562 cell line, as standard NK target cells, was engineered to stably express enhanced green fluorescent protein (EGFP), which can be quantified by flow cytometry. The EGFP-flow cytometry method for measuring NK cell activity was improved by double staining of early and late apoptotic target cells. Whole-blood samples from healthy volunteers were assessed with this method, which demonstrated that optimal conditions were effector-target ratio of 10:1 and incubation time of 4 h. This method was further evaluated for samples from 113 HLH patients and 64 healthy volunteers. Mean NK cell activity in either primary or secondary HLH patients was significantly lower (P < 0.001) than in healthy individuals (20.23 ± 4.12%). Furthermore, primary HLH patients (10.76 ± 2.54%) exhibited even lower (P < 0.001) NK cell activity compared with secondary HLH patients (15.01 ± 3.62%). We have optimized and implemented this method in clinically relevant samples.


Asunto(s)
Técnicas de Cocultivo/métodos , Células Asesinas Naturales/inmunología , Linfohistiocitosis Hemofagocítica/inmunología , Adulto , Femenino , Proteínas Fluorescentes Verdes/inmunología , Humanos , Células K562 , Células Asesinas Naturales/patología , Linfohistiocitosis Hemofagocítica/patología , Masculino
8.
J Cancer Res Clin Oncol ; 143(4): 661-671, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28168356

RESUMEN

BACKGROUND: Long noncoding RNAs (lncRNAs) can act as competitive endogenous RNAs (ceRNAs) to compete with mRNAs for binding miroRNAs (miRNAs). The dysregulated triplets, composed by mRNAs, lncRNAs, and miRNAs, contributed to the development and progression of diseases, such as cancer. However, the roles played by triplet biomarkers are not fully understand in glioblastoma multiforme (GBM) patient survival. OBJECTIVES: Here, we constructed a differential triplet interaction network (TriNet) between GBM and normal tissues and identified GBM survival related triplets. METHODS: Four significantly dysregulated modules, enriched differentially expressed molecules, were identified by integrating affinity propagation method and hypergeometric method. Furthermore, knockdown of TP73-AS1 was implemented by siRNA and the expression of RFX1 was examined in U87 cells by qRT-PCR. The apoptosis of U87 cells was investigated using MTT assay and Acridine orange/Ethidium bromide (AO/EB) assay. RESULTS: We randomly split GBM samples into training and testing sets, and found that these four modules can robustly and significantly distinguish low- and high-survival patients in both two sets. By manually curated literatures for triplets mediated by core interactions, we found that members involved tumor invasion, proliferation, and migration. The dysregulated triplets may cause the poor survival of GBM patients. We finally experimentally verified that knockdown of TP73-AS1, an lncRNA of one triplet, could not only reduce the expression of RFX1, an mRNA of this triplet, but also induce apoptosis in U87 cells. CONCLUSIONS: These results can provide further insights to understand the functions of triplet biomarkers that associated with GBM prognosis.


Asunto(s)
Neoplasias Encefálicas/genética , Glioblastoma/genética , Análisis de Supervivencia , Neoplasias Encefálicas/patología , Glioblastoma/patología , Humanos , Sistemas de Lectura Abierta
9.
Oncol Res ; 25(6): 1009-1019, 2017 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-28244850

RESUMEN

Pyroptosis is a type of proinflammatory programmed cell death mediated by caspase 1 activity and occurs in several types of eukaryotic tumor cells, including gliomas. MicroRNAs (miRNAs), small endogenous noncoding RNAs, have been demonstrated to be advantageous in glioma therapy. However, the question of whether miRNAs regulate pyroptosis in glioma remains unknown. The current study found that caspase 1 expression was substantially increased in both glioma tissues and glioma cell lines, U87 and T98G, while miR-214 expression was significantly downregulated. Luciferase reporter assay recognized caspase 1 as a target gene of miR-214. These findings demonstrate that miR-214 could inhibit cell proliferation and migration through the regulation of pyroptosis intermediated by caspase 1 in glioma U87 and T98G cells and may suggest a novel therapeutic for the intervention of glioma.


Asunto(s)
Neoplasias Encefálicas/patología , Caspasa 1/metabolismo , Glioma/patología , MicroARNs/genética , Piroptosis/genética , Neoplasias Encefálicas/genética , Caspasa 1/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Humanos
10.
Zhonghua Xue Ye Xue Za Zhi ; 36(6): 507-10, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26134018

RESUMEN

OBJECTIVE: To investigate the outcomes, survival status, and the prognostic factors of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) patients. METHODS: A retrospective study was carried out to analyze the clinical data of 61 EBV-HLH cases, from January 2008 to July 2014. Prognostic factors were analyzed through COX model (single factor and multiple factors). RESULTS: A total of 246 patients with HLH were diagnosed, among which 102 cases were with EBV infection (including 61 EBV-HLH, 36 lymphoma associated HLH, 5 primary HLH. Among the 61 cases, 40 were male and 21 were female, with a ration of 1.9:1. The median age was 28 years (range, 12-78). 1, 3, 6 and 12-month overall survival rates of 61 EBV-HLH were 65.6%, 47.5%, 32.4%, and 25.0%, respectively. The median follow-up time was 3 (0.5-28) months. 12 patients didn't use etoposide within 4 weeks after diagnosis, while HLH-94 protocol was used in 33 patients and HLH-2004 protocol was used in 16 patients. Response rates of theses three groups were 33.3%, 51.5%, and 43.8%, respectively (P=0.401). There was statistically difference between the group without etoposide and the HLH-94/ HLH-2004 group in the overall survival rate (P=0.033). Serum albumin level (P=0.033) and whether EBV could became negative (P=0.010) were independent predictors for EBV-HLH. CONCLUSION: EBV-HLH patients have severe clinical feature and poor prognosis. Early application of immune chemotherapy based on etoposide can improve survival. Serum albumin level and whether EBV can become negative are independent prognostic factors for survival.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Linfohistiocitosis Hemofagocítica , Adolescente , Adulto , Anciano , Niño , Etopósido , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
11.
Zhonghua Xue Ye Xue Za Zhi ; 35(9): 796-801, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25246246

RESUMEN

OBJECTIVE: To analyze the clinical manifestations, laboratory data, therapy, and prognosis in patients with hemophagocytic lymphohistiocytosis (HLH). METHODS: A retrospective study was carried out in 192 adult patients with HLH between 2003 and 2013. RESULTS: Of the 192 cases, 70 cases were secondary to cancer and 64 cases secondary to infection. According to HLH-2004 criteria, the coincidence rate of indices were: fever (98.96%), high level of serum ferritin (94.27%), increased level of soluble interleukin- 2 receptor(sCD25) (94.79%), decreased or absent activity of NK cells (94.27%), cytopenias (80.73%), splenomegaly (80.21%), emophagocytosis in bone marrow, spleen or lymph nodes (74.48%), hypofibrinogenemia (50.52%), hypertriglyceridemia (37.50%). In addition, 94.27% of patients were presented with liver dysfunction, 96.35% with infections, and 75.52% with coagulopathy. Incidences of central nervous system symptoms and rash were 19.27% and 20.31%, respectively. Among cancer, infection and rheumatic group, there were statistically differences on white blood cells (WBC), platelet (PLT), sCD25, alanine aminotransferase, aspartate aminotransferase, total bilirubin and globulin(GLO) (P<0.05). The differences of WBC, PLT, albumin (ALB), GLO, brain natriuretic peptide, creatinine, urea nitrogen between survival group and death group had statistical significance. CONCLUSION: The secondary HLH occurs from various underlined diseases. Cancer, especially T- cell lymphoma, is the main cause, Secondly, it is EB virus infection. The diagnostic sensitive indicators are Persistent fever, higher level of serum ferritin, low or absent NK-cell activity, and increased sCD25 were the most valuable parameters for diagnosis. Cytopenias were not common in early phase of HLH secondary to rheumatic diseases. WBC, PLT, ALB, GLO could be used as the preliminary parameters for diagnosis. Cardiac insufficiency, renal insufficiency and coagulation dysfunction play important roles in prognosis.


Asunto(s)
Linfohistiocitosis Hemofagocítica , Adulto , Médula Ósea , Fiebre , Humanos , Células Asesinas Naturales , Pronóstico , Estudios Retrospectivos
12.
Se Pu ; 28(7): 724-8, 2010 Jul.
Artículo en Zh | MEDLINE | ID: mdl-21046796

RESUMEN

The back-flush technique was used in the determination of organophosphorus pesticide residues in vegetables by gas chromatography. The pesticide residues were extracted with acetonitrile and sodium chloride under mechanical shaking, and separated by centrifuging and partitioning. The extract was analyzed by gas chromatograph equipped with a flame photometric detector and a micro fluidic device with back-flush function. The results showed that the 16 organophosphorus pesticides have good linearity within the concentration range of 0.040 -3.20 mg/L. The recoveries varied from 75.2% to 111.5%, with the relative standard deviations (RSDs) in the range of 2.8% - 10.4%. The detection limits of these target compounds were from 0.003 to 0.01 mg/kg. The application of back-flush technique in this method significantly reduced the cycle time and matrix effect and improved the analysis efficiency.

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