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1.
Phys Rev E ; 108(5-2): 055208, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38115494

RESUMO

We report a proposal to observe the two-photon Breit-Wheeler process in plasma driven by compact lasers. A high-charge electron bunch can be generated from laser plasma wakefield acceleration when a tightly focused laser pulse propagates in a subcritical density plasma. The electron bunch scatters with the laser pulse coming from the opposite direction and resulting in the emission of high brilliance x-ray pulses. In a three-dimensional particle-in-cell simulation with a laser pulse of ∼10 J, one could produce an x-ray pulse with a photon number higher than 3×10^{11} and brilliance above 1.6×10^{23} photons/s/mm^{2}/mrad^{2}/0.1%BW at 1 MeV. The x-ray pulses collide in the plasma and create more than 1.1×10^{5} electron-positron pairs per shot. It is also found that the positrons can be accelerated transversely by a transverse electric field generated in the plasma, which enables the safe detection in the direction away from the laser pulses. This proposal enables the observation of the linear Breit-Wheeler process in a compact device with a single shot.

2.
Artigo em Chinês | MEDLINE | ID: mdl-37599236

RESUMO

Objective: To study the effect of trefoil factor family (TFF) 3 on the expression of tight junctions (TJs) in the nasal mucosa epithelium of eosinophilic chronic rhinosinusitis (eCRS) and its mechanism. Methods: From September to December 2020, eligible patients from the Department of Otorhinolaryngology of the First Affiliated Hospital of Nanchang University were recruited, including 11 control patients and 37 patients with chronic rhinosinusitis with nasal polyps (CRSwNP), from whom nasal mucosa and nasal polyp tissue samples were collected. Immunohistochemistry (IHC) was used to detect the localization and expression intensity of TFFs (TFF1, TFF2 and TFF3) and TJs (occudin, claudin-1 and ZO-1) in nasal mucosa. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) were used to detect the mRNA and protein expression. A cell model of tight junction injury in human nasal epithelial cells (HNECs) through stimulation with interleukin (IL)-13 was also established. The optimal modeling concentration and time for HNECs were determined, which were subsequently treated with TFF3 and/or a phosphoinositide 3-kinase (PI3K)-specific inhibitor (LY294002). Finally, RT-qPCR and WB were used to assess the effects of TFF3 on tight junctions and the PI3K/serine/threonine kinase (Akt) signaling pathway. Data were analyzed statistically using GraphPad Prism 7 software. Results: IHC results showed that the expression of TFF1 and TFF3 in nasal mucosa of eCRS group was significantly higher than that of control group (t=4.62, P=0.002; t=5.89, P<0.001), respectively, mainly expressed in goblet cell. The expression of occludin, claudin-1 and ZO-1 in the nasal mucosa of the eCRS group was lower than that of the control group (occludin t=3.98, P=0.019; claudin-1 t=5.15, P=0.002; ZO-1 t=5.42, P=0.001), respectively. WB results showed that the expression of TFF3 in non-eosinophilic chronic sinusitis (Non-eCRS) group and eCRS group was higher than that in the control group (t=3.62, P=0.036; t=5.93, P<0.001). The expression of occludin, claudin-1 and ZO-1 in eCRS group was lower than that in the control group (occludin t=5.14, P=0.002; claudin-1 t=6.35, P<0.001; ZO-1 t=6.64, P<0.001), respectively. The RT-qPCR results showed that compared with the control group, the levels of TFF1 and TFF3 mRNA were increased in the nasal mucosal epithelium of the Non-eCRS and eCRS groups (TFF1 t=3.98, P=0.046, t=4.89, P=0.002; TFF3 t=3.50, P=0.044, t=6.78, P<0.001). There was no statistically significant difference in TFF2 mRNA levels between the Non-eCRS and eCRS groups (t=1.34, P=0.061; t=3.37, P=0.055). Compared with the control group, Non-eCRS and eCRS groups showed a decrease in the mRNA levels of occludin, claudin-1 and ZO-1 (occludin t=4.27, P=0.011, t=5.61, P=0.007; claudin-1 t=3.62, P=0.036, t=6.80, P<0.001; ZO-1 t=3.47, P=0.047, t=7.86, P<0.001). The mRNA levels of TFF3 and TJs in eCRS nasal mucosa tissue showed a moderate positive correlation (occludin r=0.661, claudin-1 r=0.614, ZO-1 r=0.548, all P<0.001); TFF1 showed a low degree of positive correlation with the expression of occludin, claudin-1 and ZO-1 (occludin r=0.467, P=0.040; claudin-1 r=0.362, P=0.012; ZO-1 r=0.425, P=0.025). The establishment of cell models showed that compared with normal HNECs, the mRNA expression of TFF3 was most significantly increased at a concentration of 50 ng/ml stimulated by IL-13 (t=3.72, P=0.013); The mRNA expression of occludin, claudin-1 and ZO-1 decreased (occludin t=3.18, P=0.031; claudin-1 t=3.86, P=0.010; ZO-1 t=5.16, P=0.002). The expression of TFF3 mRNA increased most significantly after 15 hours of IL-13 stimulation (t=3.14, P=0.034); The mRNA expression of occludin, claudin-1 and ZO-1 decreased (occludin t=3.97, P=0.010; claudin-1 t=4.78, P=0.004; ZO-1 t=5.16, P=0.004). TJs damage model could be established by treating HNECs with 50 ng/ml IL-13 for 15 hours. Intervention experiments showed that compared with the IL-13 group, the IL-13+TFF3 group showed an increase in TJs mRNA expression (occludin t=6.10, P=0.009; claudin-1 t=5.90, P=0.013; ZO-1 t=9.44, P=0.007). Compared with the IL-13 group, the expression of TJs protein in the IL-13+TFF3 group increased (occludin t=3.23, P=0.013; claudin-1 t=9.40, P=0.017; ZO-1 t=2.23, P=0.032); The expression of TJs protein decreased in the IL-13+TFF3+LY294002 group (occludin t=4.73, claudin-1 t=8.77, ZO-1 t=3.51, all P<0.001). Compared with the IL-13+TFF3 group, the IL-3+TFF3+LY294002 group showed a decrease in PI3K and p-Akt/Akt protein expression (PI3K t=13.29, p-Akt/Akt t=10.30, all P<0.001). The increased mRNA and protein expression of occludin, claudin-1 and ZO-1 induced by TFF3 were also inhibited by LY294002. Conclusion: TFF3 can up-regulate the expression of occludin, claudin-1, and ZO-1 through PI3K/Akt pathway, and has a certain protective effect on the nasal mucosal epithelial barrier, providing a new idea for treating eCRS.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas de Junções Íntimas , Humanos , Ocludina , Claudina-1 , Interleucina-13 , Proteínas Proto-Oncogênicas c-akt , Doença Crônica , Fator Trefoil-3
3.
Opt Lett ; 48(9): 2433-2436, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126291

RESUMO

Extremely strong terahertz (THz) waves are desperately demanded for investigating nonlinear physics, spectroscopy, and imaging in the THz range. However, traditional crystal-/semiconductor-based THz sources have limitations of reaching extremely high amplitude due to the damage threshold of devices. Here, by introducing Raman amplification to the THz range, we propose a novel, to the best of our knowledge, scheme to amplify THz waves in plasma. A long-pulse CO2 pump laser transfers its energy to a multicycle, 10-THz seed in a two-step plasma. By one-dimensional simulations, a 0.87-GV/m, 1.2-ps-duration THz seed is amplified to 10 GV/m in a 5.7-mm-long plasma with an amplification efficiency approaching 1%. The method provides a new technology to manipulate the intensity of THz waves.

4.
Zhonghua Yi Xue Za Zhi ; 102(15): 1100-1107, 2022 Apr 19.
Artigo em Chinês | MEDLINE | ID: mdl-35436809

RESUMO

Objectives: To explore the risk factors associated with septic cardiomyopathy and establish a predictive model of the disease based on left ventricular global longitudinal strain (LV GLS). Methods: Data from sepsis patients without a history of cardiac dysfunction who were treated in the Critical Care Department of the Northern Jiangsu People's Hospital from September, 2019 to January, 2021 were included in the analysis. The LV GLS was measured by echocardiography within 72 hours and the patients were divided into a septic myocardiopathy group (LV GLS>-17%) and a normal cardiac function group (LV GLS≤-17%). Clinical data from two groups of patients were collected for univariate analysis. The receiver operating characteristic (ROC) curves of the factors that were statistically different were drawn for exploring the diagnostic and cut-off values. The continuous variable was converted to a dichotomous variable according to the cut-off value. Multivariate logistic regression analysis of sepsis cardiomyopathy was performed to screen the risk factors and create a predictive model. The predictive model was evaluated by ROC curve analysis and the Bootstrap method and shown as a nomograph. Results: Patients in the sepsis cardiomyopathy group had higher levels of high sensitive troponin I (Hs-TnI), procalcitonin (PCT), lactate (Lac), N-terminal pro-brain atriuretic peptide (NT-proBNP), vasopressor dosing intensity (VDI) and sequential organ failure assessment (SOFA) when compared to those in the normal cardiac function group (all P<0.05). The multivariate logistic regression analysis showed that Hs-TnI≥0.131 µg/L (OR=6.71, 95%CI:2.67-16.88, P<0.001), PCT≥40 µg/L (OR=3.08, 95%CI:1.10-8.59, P=0.032), Lac≥4.2 mmol/L (OR=2.80, 95%CI:1.02-7.69, P=0.045), NT-proBNP≥3 270 ng/L (OR=2.67, 95%CI:1.06-6.74, P=0.038) were independent risk factors for septic myocardiopathy. The area under the ROC curve of the predictive model based on the four indexes up-mentioned was 0.838 (95%CI:0.766-0.910), and the C-index was 0.822 (95%CI:0.750-0.894) which indicated the utility of the nomogram. The model had a good predictive ability, accuracy and discrimination. Conclusions: Hs-TnI≥0.131 µg/L, PCT≥40 µg/L, Lac≥4.2 mmol/L and NT-proBNP≥3 270 ng/L are independent risk factors for septic myocardiopathy, and the septic cardiomyopathy predictive model constructed based on these factors has a good diagnostic performance.


Assuntos
Cardiomiopatias , Sepse , Humanos , Ácido Láctico , Pró-Calcitonina , Prognóstico , Curva ROC , Estudos Retrospectivos
5.
Opt Lett ; 47(7): 1658-1661, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363702

RESUMO

We propose a new, to the best of our knowledge, method to radiate a high-efficiency and collimated terahertz (THz) pulse from a relativistic femtosecond laser and cone target. Particle-in-cell simulations demonstrate that a THz source of 40 mJ, pointing at an angle of ∼20 ∘, can be generated from a laser pulse of 1.9 J by using a cone target whose open angle is 10 ∘. The peak power of the THz pulse is 1011 W. This method, which manipulates the divergence angle and the energy conversion efficiency of the THz source, should promote THz science into the extra strong region with a compact laser system.

7.
Zhonghua Xue Ye Xue Za Zhi ; 42(8): 646-653, 2021 Aug 14.
Artigo em Chinês | MEDLINE | ID: mdl-34547870

RESUMO

Objective: To evaluate the prognostic significance of clonal gene mutations using next-generation sequencing in patients with core-binding factor acute myeloid leukemia (CBF-AML) who achieved first complete remission after induction chemotherapy. Methods: The study, which was conducted from July 2011 to August 2017 in First Affiliated Hospital of Soochow University, comprised 195 newly diagnosed patients with CBF-AML, including 190 patients who achieved first complete remission after induction chemotherapy. The cohort included 134 patients with RUNX1-RUNXIT1(+) AML and 56 patients with CBFß-MYH11(+) AML. The cohort age ranged from 15 to 64 years, with a median follow-up of 43.6 months. Overall survival (OS) and disease-free survival (DFS) were assessed by the log-rank test, and the Cox proportional hazards regression model was used to determine the effects of clinical factors and genetic mutations on prognosis. Results: The most common genetic mutations were in KIT (47.6% ) , followed by NRAS (20.0% ) , FLT3 (18.4% ) , ASXL2 (14.3% ) , KRAS (10.7% ) , and ASXL1 (9.7% ) . The most common mutations involved genes affecting tyrosine kinase signaling (76.4% ) , followed by chromatin modifiers (29.7% ) . Among the patients receiving intensive consolidation therapy, the OS tended to be better in patients with CBFß-MYH11(+) AML than in those with RUNX1-RUNXIT1 (+) AML (P=0.062) . Gene mutations related to chromatin modification, which were detected only in patients with RUNX1-RUNXIT1(+) AML, did not affect DFS (P=0.557) . The patients with mutations in genes regulating chromatin conformation who received allo-hematopoietic stem cell transplantation (allo-HSCT) achieved the best prognosis. Multivariate analysis identified KIT exon 17 mutations as an independent predictor of inferior DFS in patients with RUNX1-RUNXIT1(+) AML (P<0.001) , and allo-HSCT significantly prolonged DFS in these patients (P=0.010) . Conclusions: KIT exon 17 mutations might indicate poor prognosis in patients with RUNX1-RUNXIT1(+) AML. Allo-HSCT may improve prognosis in these patients, whereas allo-HSCT might also improve prognosis in patients with mutations in genes related to chromatin modifications.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Proteínas Proto-Oncogênicas c-kit/genética , Adolescente , Adulto , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Pessoa de Meia-Idade , Mutação , Prognóstico , Adulto Jovem
9.
Zhonghua Yi Xue Za Zhi ; 100(21): 1662-1667, 2020 Jun 02.
Artigo em Chinês | MEDLINE | ID: mdl-32486603

RESUMO

Objective: To observe the effect of different modes of mechanical ventilation on patient-ventilator synchrony and diaphragm function in rabbits with acute respiratory distress syndrome(ARDS). Methods: Eighteen New Zealand rabbit models of ARDS were induced by intratracheal infusion hydrochloric acid until the oxygenation index (PaO(2)/FiO(2)) was less than 200 mmHg, and then divided into three groups with random number: assisted-controlled mechanical ventilation (A/C) group, pressure support ventilation (PSV) group and neurally adjusted ventilatory assist (NAVA) group. All of them were ventilated for four hours with the targeted tidal volume (V(T)) (6 ml/kg) and the positive end-expiratory pressure (PEEP) titrated with the maximum oxygenation method. Gas exchange, pulmonary mechanics and patient-ventilator synchrony were determined during 4 h of ventilation and the concentrations of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) in diaphragm were measured after 4 h of ventilation. The q test was used for the multiple comparison of the sample mean. Results: There were no significant differences in PaO(2)/FiO(2) between three groups during ventilation 1-4 h (F=1.029, P>0.05). The V(T) in NAVA group was obviously lower than that in PSV group and the respiratory rate (RR) and the electrical activity of diaphragm(EAdi) were higher than those in A/C group(all P<0.05).The trigger delay and off cycle delay the in NAVA group were markedly lower than those in A/C and PSV group during ventilation 1-4 h(F=14.312, 9.342, both P<0.05). Asynchrony index in NAVA group (3.1%±1.0%) was obviously lower than those in A/C group (22.3%±5.2%) and PSV group(8.4%±2.3%) (F=7.192, P<0.05). In NAVA group, peak EAdi (EAdi(peak)) and peak airway pressure (Ppeak) were markedly correlated (r=0.97±0.16, P<0.05), while Ppeak delivery in A/C and PSV group was not correlated to EAdi(peak) (r=0.38±0.13,0.46±0.15, both P>0.05).Compared with A/C group, the concentration of MDA in the diaphragm in NAVA group was obviously lower(P<0.05). SOD and GSH level inthe diaphragm in NAVA group were both obviously higher than those in A/C group (both P<0.05). Conclusions: It is helpful to avoid eccentric contraction of diaphragm, lessen oxidative stress and alleviate ventilator-related diaphragm dysfunction by keeping spontaneous breathing as far as possible and subject-ventilator synchrony when ventilation in ARDS with NAVA.


Assuntos
Diafragma , Síndrome do Desconforto Respiratório , Animais , Humanos , Coelhos , Respiração Artificial , Ventiladores Mecânicos
10.
Zhonghua Xue Ye Xue Za Zhi ; 41(3): 210-215, 2020 Mar 14.
Artigo em Chinês | MEDLINE | ID: mdl-32311890

RESUMO

Objective: To investigate the prognostic value of clonal gene mutations detected by second-generation sequencing in patients with positive RUNX1-RUNX1T1 acute myeloid leukemia (AML) who received high-dose chemotherapy or autologous transplantation (intensive consolidation therapy) in the first complete remission (CR(1)) state. Methods: 79 AML patients with positive RUNX1-RUNX1T1 who received intensive consolidation therapy in CR(1) state from July 2011 to August 2017 were analyzed retrospectively. Kaplan-Meier curve and Cox regression model were used to figure out the effect of leukocyte counts at onset and gene mutations for prognosis. Results: C-KIT, FLT3, CEBPA and DNMT3A gene mutations were found in 25 (31.6%) , 6 (7.6%) , 7 (8.9%) and 1 (1.3%) patient among the population. Mutations in C-KIT exon17 and C-KIT exon8 were detected in 19 (24.1%) and 5 (6.3%) cases, respectively, and mutations of FLT3-ITD were confirmed in 5 (6.3%) cases. The higher leukocyte counts presented at onset of leukemia, the shorter overall survival (OS) was seen in these patients (P=0.03) . Patients with C-KIT exon17 mutation had significantly shorter OS (P=0.01) and disease free survival (DFS) (P=0.006) compared with those without gene mutations, and patients with FLT3-ITD gene mutation got the inferior OS (P=0.048) and DFS (P=0.071) . Conclusion: In AML patients with positive RUNX1-RUNX1T1 receiving intensive consolidation therapy, the white blood cell counts at onset of leukemia, C-KIT mutations in exon 17, and FLT3-ITD gene mutations suggest poor prognosis, which would contribute to elaborate risk stratification, personalized treatment and predict prognosis for these patients.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda , Proteína 1 Parceira de Translocação de RUNX1/genética , Quimioterapia de Consolidação , Humanos , Leucemia Mieloide Aguda/genética , Mutação , Prognóstico , Estudos Retrospectivos , Tirosina Quinase 3 Semelhante a fms
11.
Artigo em Chinês | MEDLINE | ID: mdl-31550756

RESUMO

Objective: To check Forkhead box M1 (FoxM1) expression in nasal mucosal of chronic rhinosinusitis (CRS) patients and the effect of inflammatory factors on FoxM1 expression, in order to research the significance of FoxM1 in CRS. Methods: From January to October of 2018, 50 patients hospitalized in the Department of Otorhinolaryngology, Head and Neck Surgery, First Affiliated Hospital of Nanchang University were enrolled in this study. Twenty CRS patients with polyps (CRSwNP), 20 CRS patients without nasal polyps (CRSsNP) and 10 patients with simple deviation of nasal septum (the control groups) were selected. The expression of FoxM1 in nasal mucosa of these patients was detected by immunohistochemistry (IHC) and real-time fluorescent quantitative PCR (qRT-PCR). Meanwhile, HE stain was used to observe the pathologic changes in each sample. By establishing human nasal epithelium cells cultivating model in vitro and identifying via immumofluorescence method, experimental group and control group were set up, then activation factors including interleukin (IL)-1ß, IL-4, IL-5, IL-17, interferon-γ (IFN-γ) and staphylococcal entemtoxin B (SEB) were added in the models after stabilizing passage, and qRT-PRC and Western blot method were applied to check the expressing change of FoxM1. Software SPSS 18.0 was used for statistical analysis. Results: HE stain showed that the mainly pathologic change in nasal mucosa of CRS patients with or without nasal polyp was mucosal epithelial cells, goblet cell and submucosal gland hyperplasia, accompanied by a large number of inflammatory cells infiltration. The result of IHC demonstrated that both of the expression of FoxM1 in nasal mucosal tissue of CRS patients in the CRSwNP and CRSsNP groups exceed that of the control group (80% vs 75% vs 20%, χ(2) value was 10.000, 8.213, respectively, all P<0.05); there was no difference of expression between the two groups of CRS patients (χ(2)=0.143, P>0.05). The result of qRT-PCR demonstrated that the expression of FoxM1 mRNA in nasal mucosa of CRSwNP and CRSsNP was increased compared with that of the control group (3.309±1.511 vs 3.261±1.336 vs 1.000±0.774, t value was 4.519, 4.928, respectively, all P<0.05), but the difference between the two groups of CRS patients had no statistic significance (t=0.107, P=0.909). Nasal mucosa epithelial cells cultivating models was established successfully. Q-RT PCR and Western blot were conducted after stimulation of 100 ng/ml IL-1ß, IL-4, IL-5, IL-17, IFN-γ and SEB for 36 h, and the proteins expression levels of FoxM1 exceeded the groups without stimulation with statistic significance. Conclusions: The expression of FoxM1 in CRS increases and many types of cytokine can induce the increase of FoxM1 in human nasal epithelial cells. FoxM1 may participate in the process of pathogenesis in CRS.


Assuntos
Proteína Forkhead Box M1 , Regulação da Expressão Gênica , Mucosa Nasal , Rinite , Sinusite , Doença Crônica , Citocinas , Proteína Forkhead Box M1/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Humanos , Mucosa Nasal/fisiopatologia , Pólipos Nasais , Rinite/fisiopatologia , Sinusite/fisiopatologia
12.
Artigo em Chinês | MEDLINE | ID: mdl-30970402

RESUMO

Objective:To investigate the expression of microtubuleassociated protein 1 light chain 3 beta(LC3) and eosinophil cationic protein in allergic rhinitis(AR) for further understanding of the pathogenesis of AR. Method: Twenty cases of normal nasal mucosa and 20 cases of AR nasal mucosa were collected. Histological changes of nasal mucosa were examined by hematoxylin and eosin(HE) staining. The expression of LC3 and ECP were measured by immunohistochemistry(IHC) and Western Blot(WB). Result: The tissue samples demonstrated a large number of eosinophils and lymphocytes infiltration in AR. IHC revealed that LC3 and ECP expression were higher in AR than in normal nasal mucosa(P<0.05). WB also showed that the relative expression levels of protein expression of LC3 and ECP were greater in AR than in controls. The expression level of LC3 was positively correlated with that of ECP protein in AR. Conclusion: LC3 and ECP were upregulated and positively correlated in AR, indicating that autophagy plays an important role in the toxicity of allergic rhinitis , which provides theoretical basis for the precise treatment of AR.


Assuntos
Proteína Catiônica de Eosinófilo , Proteínas Associadas aos Microtúbulos , Rinite Alérgica , Autofagia , Proteína Catiônica de Eosinófilo/metabolismo , Eosinófilos , Humanos , Contagem de Leucócitos , Proteínas Associadas aos Microtúbulos/metabolismo , Mucosa Nasal , Rinite Alérgica/metabolismo
13.
Phys Rev Lett ; 122(1): 014803, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012707

RESUMO

We report the experimental generation of highly energetic carbon ions up to 48 MeV per nucleon by shooting double-layer targets composed of well-controlled slightly underdense plasma and ultrathin foils with ultraintense femtosecond laser pulses. Particle-in-cell simulations reveal that carbon ions are ejected from the ultrathin foils due to radiation pressure and then accelerated in an enhanced sheath field established by the superponderomotive electron flow. Such a cascaded acceleration is especially suited for heavy ion acceleration with femtosecond laser pulses. The breakthrough of heavy ion energy up to many tens of MeV/u at a high repetition rate would be able to trigger significant advances in nuclear physics, high energy density physics, and medical physics.

14.
Phys Rev Lett ; 122(1): 014802, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012720

RESUMO

A novel approach is proposed to demonstrate the two-photon Breit-Wheeler process by using collimated and wide-bandwidth γ-ray pulses driven by 10-PW lasers. Theoretical calculations suggest that more than 3.2×10^{8} electron-positron pairs with a divergence angle of 7° can be created per shot, and the signal-to-noise ratio is higher than 10^{3}. The positron signal, which is roughly 100 times higher than the detection limit, can be measured by using the existing spectrometers. This approach, which could demonstrate the e^{-}e^{+} pair creation process from two photons, would provide important tests for two-photon physics and other fundamental physical theories.

15.
Phys Rev E ; 100(6-1): 063203, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31962419

RESUMO

A deflection effect of an intense laser beam with spin angular momentum is revealed theoretically by an analytical modeling using radiation pressure and momentum balance of laser plasma interaction in the relativistic regime as a deviation from the law of reflection. The reflected beam deflects out of the plane of incidence with a deflection angle up to several milliradians, when a nonlinear polarized laser, with the intensity I_{0}∼10^{19}W/cm^{2} and duration around tens of femtoseconds, is obliquely incident and reflected by an overdense plasma target. This effect originates from the asymmetric radiation pressure caused by spin angular momentum of the laser photons. The dependence of the deflection angle of a Gaussian-type laser on the parameters of laser pulse and plasma foil is theoretically derived, which is also confirmed by three-dimensional particle-in-cell simulations of circularly polarized laser beams with the different intensity and pulse duration.

16.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 32(15): 1199-1202, 2018 Aug 05.
Artigo em Chinês | MEDLINE | ID: mdl-30282159

RESUMO

Thyroid cancer is a common malignancy derived from the endocrine system and the incidence of thyroid cancer is on the rise. Papillary thyroid carcinoma (PTC) is the most common type, and 90% of PTC patients have long-term survival, but the recurrence rate is still as high as 30%. Current diagnostic and postoperative monitoring techniques have been developed, but their negative rates and interfering factors also occupy an absolute proportion, and lack specific markers for the prognosis of PTC. Studies have shown that microRNAs (miRNAs) are associated with the development, metastasis and invasiveness of PTC and as a biomarker to aid in the diagnosis and monitoring of recurrence, and to determine the prognosis for specific markers. The future of PTC diagnosis, treatment and improve prognosis has broad prospects. This review mainly describes the development of miRNA as biomarkers for the diagnosis, recurrence and prognosis of PTC.

17.
Artigo em Chinês | MEDLINE | ID: mdl-29775032

RESUMO

Chronic rhinosinusitis (CRS) is a common disease of otorhinolaryngology head and neck surgery, manifested as nasal-sinus mucosal chronic inflammation. However, the pathogenesis of CRS is not clear. There are studies found that microRNA (miRNA) involved in CRS gene regulation. In this review, we summarize the expression of miRNAs in CRS, with the in-depth study of the role of miRNAs in CRS, and will further elucidate the pathogenesis of CRS.


Assuntos
MicroRNAs/metabolismo , Rinite/metabolismo , Sinusite/metabolismo , Doença Crônica , Humanos , Mucosa Nasal , Pólipos Nasais , Rinite/patologia , Sinusite/patologia
18.
Eur J Pain ; 22(3): 492-500, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29226545

RESUMO

BACKGROUND: The aim of this study was to assess the efficacy of a fixed nitrous oxide/oxygen mixture for the management of breakthrough cancer pain. METHODS/DESIGN: A double-blind, placebo-controlled, randomized clinical trial was undertaken in the Medical ward of Tumor Hospital of General Hospital of Ningxia Medical University. 240 cancer patients with breakthrough pain were recruited and randomly received a standard pain treatment (morphine sulphate immediate release) plus a pre-prepared nitrous oxide/oxygen mixture, or the standard pain treatment plus oxygen. The primary endpoint measure was the numerical rating scale (NRS) score measured at baseline, 5 and 15 min after the beginning of treatment, and at 5 min post treatment. RESULT: In all, analysis of pain score (NRS) at 5 min after the beginning of treatment shown a significant decrease in nitrous oxide/oxygen mixture treated patients with 2.8 ± 1.3 versus 5.5 ± 1.2 in controls (p < 0.01). At 15 min during the intervention, the mean pain score for nitrous oxide/oxygen was 2.0 ± 1.1 compared with 5.6 ± 1.3 for oxygen (p < 0.01). CONCLUSION: This study shows that self-administered nitrous oxide/oxygen mixture was effective in reducing moderate to severe breakthrough pain among patients with cancer. SIGNIFICANCE: The management of breakthrough cancer pain is always a challenge due to its temporal characteristics of rapid onset, moderate to severe in intensity, short duration (median 30-60 min). Our study find that self-administered nitrous oxide/oxygen mixture was effective in reducing moderate to severe breakthrough cancer pain.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Dor Irruptiva/tratamento farmacológico , Dor do Câncer/tratamento farmacológico , Óxido Nitroso/uso terapêutico , Oxigenoterapia/métodos , Adulto , Idoso , Analgesia , Analgésicos Opioides/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Hipestesia , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Manejo da Dor , Medição da Dor , Autoadministração , Fatores de Tempo
19.
Zhonghua Yi Xue Za Zhi ; 97(5): 343-346, 2017 Feb 07.
Artigo em Chinês | MEDLINE | ID: mdl-28219190

RESUMO

Objective: To assesse the efficacy and safety of procalcitonin-guided antibiotic treatment of sepsis patients in intensive care units (ICU). Methods: A prospective, randomised, controlled trial was gone in ICU of Northern Jiangsu People's Hospital.Between January 2013 and December 2015.One hundred and fifty-six patients assessed for eligibility were randomly assigned to the procalcitonin-guided group (PCT group, 79) or to regular antibiotic group (RAT group, 77). Patients who received antibiotics for presumed infection according to principle of antimicrobial usage.In the procalcitonin-guided group, a non-binding advice to discontinue antibiotics was provided if procalcitonin concentration had decreased by 90% or more of its peak value or to 0.25 µg/L or lower.In the regular antibiotic group, patients were treated according to principle of antimicrobial usage.The general status of the patient, antimicrobial drug use time, length of ICU stay, hospital stay time, number of cases of recurrence in 28 days and number of cases of death in 28 days were compared between the two groups. Results: There were no statistical significance in age, gender, blood culture positive rate, and chronic underlying diseases (P>0.05). While APACHE Ⅱ score of PCT group was (22.7±4.7) points, which was higher than that of RAT group (19.9±4.2) (P<0.05). Log Rank test results showed that the time of antimicrobial drug usage was significantly reduced in PCT group than RAT group [days: 8.3±0.3, 95% confidence interval (95%CI 7.9-9.1) vs 10.1±0.4, 95% confidence interval (95%CI 9.2-11.3), Log Rank value 31.85, P=0.000]. There was no significant difference in length of hospital stay, ICU stay time, number of cases of recurrence in 28 days and number of death in 28 days between two groups (P>0.05). Conclusion: Procalcitonin guidance stimulates reduction of duration of treatment and daily defined doses in critically ill patients with a presumed bacterial infection.This reduction does not affect the length of hospital stay, ICU stay time, number of cases of recurrence in 28 days and number of death in 28 days.


Assuntos
Sepse , Antibacterianos , Infecções Bacterianas , Biomarcadores , Calcitonina , Peptídeo Relacionado com Gene de Calcitonina , Estado Terminal , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Estudos Prospectivos , Precursores de Proteínas , Recidiva
20.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(14): 1057-1061, 2017 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-29798239

RESUMO

Objective:To investigate the expression of growth factor differentiation factor 15 (GDF15) in the nasal mucosa of patients with chronic rhinosinusitis (CRS) and its relationship with mucin 5AC(MUC5AC).Method:Fifteen patients with CRS and nasal polyps, 15 patients with CRS without nasal polyps and 15 patients with normal nasal mucosa were enrolled in the study. Hisological changes of sinonasal mucosa were examined by hematoxylin and eosin (HE) stainding. The expression of total mucins was evaluated by periodic acid Schiff staining(PAS). And the expression of GDF15 and MUC5AC were measured by immunohistochemistry (IHC), and reverse transcription polymerase chain reaction (RT-PCR).Result:The tissuse samples demonstrated mucaosal thicking, goblet cell hyperplasia, glandular hyperplasia and inflammatory cell infiltration in CRSwNP and CRSsNP. IHC revealed that GDF15 and MUC5AC expression higher in CRSwNP and CRSsNP than in normal sinus mucosa (P< 0.05). qRT-PCR also displays that the relative expression levles of mRNA exprssion of GDF15 and MUC5AC were higher in CRSwNP and CRSsNP than in controls.And the expression level of GDF15 was positively correlated with that of MUC5AC mRNA in CRS.Conclusion:GDF15 and MUC5AC were upregulated in CRS with or without nasal polyps, indicating that GDF15 is an important factor in the process of hypersecretion of MU5AC in CRS.


Assuntos
Fator 15 de Diferenciação de Crescimento/metabolismo , Mucina-5AC/metabolismo , Rinite/metabolismo , Sinusite/metabolismo , Doença Crônica , Humanos , Mucosa Nasal/metabolismo , Pólipos Nasais
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