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1.
Nature ; 621(7979): 483-486, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37674076

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-25258737

RESUMO

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.


Assuntos
Minas de Carvão/métodos , Carvão Mineral/análise , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , China , Saúde Ambiental/métodos , Geografia , Humanos , Reprodutibilidade dos Testes , Gestão da Segurança/métodos
3.
Zhonghua Yi Xue Za Zhi ; 94(36): 2841-3, 2014 Sep 30.
Artigo em Zh | MEDLINE | ID: mdl-25534103

RESUMO

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.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Viremia , Humanos , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
4.
Materials (Basel) ; 17(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063855

RESUMO

Due to the intricate and volatile nature of the service environment surrounding prestressing anchoring materials, stress corrosion poses a significant challenge to the sustained stability of underground reinforcement systems. Consequently, it is imperative to identify effective countermeasures against stress corrosion failure in cable bolts within deep underground environments, thereby ensuring the safety of deep resource extraction processes. In this study, the influence of various coatings on the stress corrosion resistance of cable bolts was meticulously examined and evaluated using specifically designed stress-corrosion-testing systems. The specimens were subjected to loading using four-point bending frames and exposed to simulated underground corrosive environments. A detailed analysis and comparison of the failure patterns and mechanisms of specimens coated with different materials were conducted through the meticulous observation of fractographic features. The results revealed stark differences in the stress corrosion behavior of coated and uncoated bolts. Notably, epoxy coatings and chlorinated rubber coatings exhibited superior anti-corrosion capabilities. Conversely, galvanized layers demonstrated the weakest effect due to their sacrificial anti-corrosion mechanism. Furthermore, the effectiveness of the coatings was found to be closely linked to the curing agent and additives used. The findings provide valuable insights for the design and selection of coatings that can enhance the durability and reliability of cable bolts in deep underground environments.

5.
Materials (Basel) ; 17(16)2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39203164

RESUMO

When modelling the anchorage performance of rebars with the tri-linear law, the calculation process of the load-deformation relation is complicated. The reason is that when the rebar-grout interface entered the elastic-softening-debonding stage, the softening section length and debonding section length vary simultaneously. To solve this issue, this paper proposes an enhanced numerical calculation method. When the rebar-grout interface entered the elastic-softening-debonding stage, the softening section length was fixed to a specific value. One loop function was created to calculate the debonding section length. With this method, the number of iteration calculations significantly decreased. The credibility of this calculation method was confirmed with experimental results. Two case studies were conducted to compare the load-deformation relation obtained with the original calculation method and enhanced calculation method. The results showed that good consistency existed between the results obtained by those two methods. This finding can significantly improve the calculation efficiency when studying the anchorage performance of rebars. Moreover, this paper provides new insight for users to optimise the modelling process of rebars.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39350423

RESUMO

BACKGROUND: It is difficult for CD19 CAR-T cells to enter solid tumors, which is one reason for their poor efficacy in lymphoma treatment. The chemokine CXCL13 secreted by stro-mal cells of the lymph nodes induces the homing of B and T lymphocytes, which express its receptor CXCR5. Preclinical trials have shown that the expression of CXCR5 on CD19 CAR-T cells can increase their migration to the tumor microenvironment and enhance their antitumor function. METHODS: We engineered the CD19 CAR-T cells to express a second receptor, CXCR5. Then, we conducted a phase I clinical trial to evaluate the safety and efficacy of CXCR5 CD19 CAR-T cells in the treatment of relapsed or refractory (R/R) B-cell lymphoma. RESULTS: We recruited 10 patients with R/R B-cell lymphoma undergoing CXCR5 CD19 CAR-T cell therapy. The objective response rate was 80%, and the complete response rate was 50%. The median follow-up time was 15.48 months (3.4-22.3 months), and the median Progression-Free Survival (PFS) time was 8.15 months (1.5-22.33 months). One patient received ASCT at 1.5 months (at PR) after infusion of CAR-T cells. The incidence of grade 1 and grade 2 Cytokine Release Syndrome (CRS) was 70% and 20%, respectively. No patient experienced grade 3 or higher levels of CRS, neurotoxicity, or infusion-related dose toxicity. CONCLUSION: The results obtained in this study suggest that CXCR5 CD19 CAR-T cells should be investigated in a trial with broader patient populations. TRIAL REGISTRATION: The trials were registered at www.chictr.org.cn as ChiCTR2100052677 and ChiCTR1900028692.

7.
Materials (Basel) ; 16(15)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37570065

RESUMO

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.

8.
Sci Rep ; 12(1): 14847, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050402

RESUMO

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.

9.
Exp Ther Med ; 14(2): 1253-1259, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28810585

RESUMO

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.

10.
Int J Hematol ; 105(6): 828-834, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28185204

RESUMO

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.


Assuntos
Técnicas de Cocultura/métodos , Células Matadoras Naturais/imunologia , Linfo-Histiocitose Hemofagocítica/imunologia , Adulto , Feminino , Proteínas de Fluorescência Verde/imunologia , Humanos , Células K562 , Células Matadoras Naturais/patologia , Linfo-Histiocitose Hemofagocítica/patologia , Masculino
11.
J Cancer Res Clin Oncol ; 143(4): 661-671, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28168356

RESUMO

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.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , Análise de Sobrevida , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Fases de Leitura Aberta
12.
Oncol Res ; 25(6): 1009-1019, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28244850

RESUMO

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.


Assuntos
Neoplasias Encefálicas/patologia , Caspase 1/metabolismo , Glioma/patologia , MicroRNAs/genética , Piroptose/genética , Neoplasias Encefálicas/genética , Caspase 1/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Humanos
13.
Zhonghua Xue Ye Xue Za Zhi ; 36(6): 507-10, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26134018

RESUMO

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.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Linfo-Histiocitose Hemofagocítica , Adolescente , Adulto , Idoso , Criança , Etoposídeo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
14.
Zhonghua Xue Ye Xue Za Zhi ; 35(9): 796-801, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25246246

RESUMO

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.


Assuntos
Linfo-Histiocitose Hemofagocítica , Adulto , Medula Óssea , Febre , Humanos , Células Matadoras Naturais , Prognóstico , Estudos Retrospectivos
15.
Se Pu ; 28(7): 724-8, 2010 Jul.
Artigo em Zh | MEDLINE | ID: mdl-21046796

RESUMO

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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