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Objective: To analyze the clinical application value of a novel magnetic navigation ultrasound (MNU) combined with digital subtraction angiography (DSA) dual-guided percutaneous transhepatic biliary drainage (PTCD) through the right hepatic duct for the treatment of malignant obstructive jaundice. Methods: Randomized controlled trial. The clinical data of 64 patients with malignant obstructive jaundice requiring PTCD through the right hepatic duct at the Hepatobiliary Center of the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province People's Hospital) from December 2018 to December 2021 were retrospectively analyzed. The MNU group (n=32) underwent puncture guided by a novel domestic MNU combined with DSA, and the control group (n=32) underwent puncture guided by traditional DSA. The operation time, number of punctures, X-ray dose after biliary stenting as shown by DSA, patients' tolerance of the operation, success rate of the operation, pre- and post-operative total bilirubin, and incidence of postoperative complications were compared between the two groups. Results: The operation time of the MNU group was significantly shorter than that of the control group [(17.8±7.3) vs. (31.6±9.9) min, t=-6.35,P=0.001]; the number of punctures in the MNU group was significantly lower [(1.7±0.6) vs. (6.3±3.9) times, t=-6.59, P=0.001]; and the X-ray dose after biliary stenting as shown by DSA in the MNU group was lower than that in the control group [(132±88) vs. (746±187) mGy, t=-16.81,P<0.001]; Five patients in the control group were unable to tolerate the operation, and two stopped the operation, however all patients in the MNU group could tolerate the operation, and all completed the operation, with a success rate of 100% (32/32) in the MNU group compared to 93.8%(30/32) in the control group; the common complications of PTCD were biliary bleeding and infection, and the incidence of biliary bleeding (25.0%, 8/32) and infection (18.8%, 6/32) in the MNU group was significantly lower than that in the control group, 53.1% (17/32) and 28.1% (9/32), respectively. Conclusion: Magnetic navigation ultrasound combined with DSA dual-guided PTCD through the right biliary system for the treatment of malignant obstructive jaundice is safe and feasible.
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Ictericia Obstructiva , Humanos , Colangiografía , Drenaje , Conducto Hepático Común , Ictericia Obstructiva/cirugía , Hígado , Fenómenos Magnéticos , Estudios Retrospectivos , Ultrasonografía IntervencionalRESUMEN
Propagation of high-current relativistic electron beam (REB) in plasma is relevant to many high-energy astrophysical phenomena as well as applications based on high-intensity lasers and charged-particle beams. Here, we report a new regime of beam-plasma interaction arising from REB propagation in medium with fine structures. In this regime, the REB cascades into thin branches with local density a hundred times the initial value and deposits its energy 2 orders of magnitude more efficiently than that in homogeneous plasma, where REB branching does not occur, of similar average density. Such beam branching can be attributed to successive weak scatterings of the beam electrons by the unevenly distributed magnetic fields induced by the local return currents in the skeletons of the porous medium. Results from a model for the excitation conditions and location of the first branching point with respect to the medium and beam parameters agree well with that from pore-resolved particle-in-cell simulations.
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Laguerre-Gaussian (LG) modes can be converted from fundamental Gaussian mode by using phase optical elements such as spiral phase plates (SPP), but the conversion efficiency is strongly reduced in high charge plates because of the transverse intensity deviation. In this paper, a three-step scheme is proposed to dramatically improve the conversion efficiency. First, a fundamental Gaussian beam is converted to a 1st-order LG beam via a 1st-order SPP and a spatial filtering system. Then, by using a periscopic axicon mirror (PAM), the lst-order LG beam is transformed into an annular beam with larger beam radius. Finally, by using a second high-order SPP, this intensity-matched ring beam can be effectively converted to a high-charge LG0l beam. Through optimization of the PAM's parameter, the total conversion efficiency from fundamental Gaussian beam to LG0l mode as high as 91.85% is obtained, which is much higher than the case without PAM. Numerical simulations are carried out by the particle-in-cell (PIC) code EPOCH to verify the effectiveness of the scheme.
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Transport of high-current relativistic electron beams in dense plasmas is of interest in many areas of research. However, so far the mechanism of such beam-plasma interaction is still not well understood due to the appearance of small time- and space-scale effects. Here we identify a new regime of electron beam transport in solid-density plasma, where kinetic effects that develop on small time and space scales play a dominant role. Our three-dimensional particle-in-cell simulations show that in this regime the electron beam can evolve into layered short microelectron bunches when collisions are relatively weak. The phenomenon is attributed to a secondary instability, on the space- and timescales of the electron skin depth (tens of nanometers) and few femtoseconds of strong electrostatic modulation of the microelectron current filaments formed by Weibel-like instability of the original electron beam. Analytical analysis on the amplitude, scale length, and excitation condition of the self-generated electrostatic fields is clearly validated by the simulations.
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MicroRNA-154 (miR-154) is dysregulated in some human malignancies and is correlated with tumor progression. However, its expression and function in non-small cell lung cancer (NSCLC) remain unclear. Therefore, we explored the effects of miR-154 on NSCLC tumorigenesis and development. Using quantitative reverse transcription-polymerase chain reaction, we detected miR-154 expression in NSCLC cell lines and primary tumor tissues. The association between miR-154 expression and clinicopathological factors was investigated, and the effects of miR-154 on the biological behavior of NSCLC cells were examined. Ultimately, the potential regulatory effect of miR-154 on high-mobility group A2 protein (HMGA2) expression was confirmed. miR-154 was significantly downregulated in NSCLC cell lines and clinical specimens. Reduced miR-154 expression was significantly associated with lymph node metastasis, advanced TNM stage, and shorter overall survival. Multivariate regression analysis confirmed that downregulation of miR-154 was an independent unfavorable prognostic factor for patients with NSCLC. Overexpression of miR-154 inhibited NSCLC cell proliferation, invasion, and migration, and promoted cell apoptosis in vitro. Furthermore, a luciferase reporter assay identified HMGA2 as a direct target of miR-154. Our findings indicate that miR-154 may act as a tumor suppressor in NSCLC and would serve as a novel therapeutic agent for miR-based therapy.
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We report and correct a couple of calculation errors in the x-ray flux and maximum peak brightness in our paper [Opt. Express 22, 32098 (2014)].
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OBJECTIVE: To assess the performance of contrast-enhanced ultrasound (CE-US) in the differential diagnosis of malignant and benign ovarian tumors. METHODS: We conducted a comprehensive literature search of PubMed and EMBASE to identify published articles evaluating the diagnostic potential of CE-US for the differentiation of benign and malignant ovarian tumors. Inclusion criteria were: (1) the study assessed the accuracy (or sensitivity and specificity) of CE-US for diagnosis of benign and malignant ovarian tumors; (2) it used surgery and histopathology as the reference standard for distinguishing between benign and malignant tumors; (3) it included data allowing construction of a 2×2 contingency table for true- and false-positives and negatives. We present summary sensitivity, specificity, diagnostic odds ratio (OR) and areas under the summary receiver-operating characteristics curves (AUCs). RESULTS: Preliminary screening identified 103 papers, of which 11 fulfilled our predefined inclusion criteria and underwent final analysis. The pooled sensitivity and specificity of CE-US for diagnosis of benign and malignant ovarian tumors were 93% (95% CI, 89-96%) and 95% (95% CI, 92-96%), respectively. The pooled diagnostic OR was 171.2 (95% CI, 65.9-444.6) and the AUC was 0.98. I(2) values of sensitivity, specificity and diagnostic OR were 38.3%, 31.7% and 48.4%, respectively, all indicating moderate heterogeneity. CONCLUSIONS: The evidence from available studies suggests CE-US is useful for discriminating between benign and malignant ovarian tumors; however, further studies are needed to examine whether CE-US has improved diagnostic test accuracy compared with that of standard two-dimensional Doppler sonography.
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Neoplasias Ováricas/diagnóstico por imagen , Lesiones Precancerosas/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Modelos Estadísticos , Oportunidad Relativa , Sensibilidad y Especificidad , UltrasonografíaRESUMEN
Generation of attosecond x-ray pulse attracts more and more attention within the advanced light source user community due to its potentially wide applications. Here we propose an all-optical scheme to generate bright, attosecond hard x-ray pulse trains by Thomson backscattering of similarly structured electron beams produced in a vacuum channel by a tightly focused laser pulse. Design parameters for a proof-of-concept experiment are presented and demonstrated by using a particle-in-cell code and a four-dimensional laser-Compton scattering simulation code to model both the laser-based electron acceleration and Thomson scattering processes. Trains of 200 attosecond duration hard x-ray pulses holding stable longitudinal spacing with photon energies approaching 50 keV and maximum achievable peak brightness up to 1020 photons/s/mm2/mrad2/0.1%BW for each micro-bunch are observed. The suggested physical scheme for attosecond x-ray pulse trains generation may directly access the fastest time scales relevant to electron dynamics in atoms, molecules and materials.
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Rayos Láser , Modelos Teóricos , Aceleradores de Partículas/instrumentación , Gases em Plasma , Procesamiento de Señales Asistido por Computador/instrumentación , Rayos X , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Dispersión de RadiaciónRESUMEN
Simultaneous generation of monoenergetic tunable protons and carbon ions from intense laser multi-component nanofoil interaction is demonstrated by using particle-in-cell simulations. It is shown that, the protons with the largest charge-to-mass ratio are instantly separated from other ion species and are efficiently accelerated in the "phase stable" way. The carbon ions always ride on the heavier oxygen ion front with an electron-filling gap between the protons and carbon ions. At the cost of widely spread oxygen ions, monoenergetic collimated protons and carbon ions are obtained simultaneously. By modulating the heavier ion densities in the foil, it is capable to control the final beam quality, which is well interpreted by a simple analytical model.
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Objective: To investigate the clinical and pathological features, treatments and prognosis of laryngeal neuroendocrine carcinoma (LNEC). Methods: We conducted the retrospective analysis of the clinical data of 12 patients with LNEC admitted to the Department of Otorhinolaryngology Head and Neck Surgery, Second Hospital of Shanxi Medical University from May 2014 to December 2021, including 9 males and 3 females, aged 50-77 years. There were 4 cases of typical carcinoid tumour (highly differentiated), 5 cases of atypical carcinoid tumour (moderately differentiated) and 3 cases of neuroendocrine small cell carcinoma (hypofractionated). The clinical features, diagnosis, treatment and prognosis of LNEC were analysed. Results: The clinical manifestations of LNEC varied according to the tumour type but did not correlate with the pathological types. The supraglottic type was characterized by sore throat, foreign body sensation in the pharynx, coughing, obstructive sensation when eating and choking on water. The treatments were determined according to the pathological types, lesion location and invasion scope. Of 12 patients 4 underwent horizontal partial laryngectomy plus elective lymphatic dissection plus postoperative radiotherapy/chemotherapy, 4 underwent vertical partial laryngectomy (3 of them with cervical lymphatic dissection), 3 underwent supported laryngoscopic plasma laryngectomy for laryngeal cancer, and 1 abandoned for treatment. With the follow-up of 8 -78 months, 5 patients were alive, 1 died from chemotherapy reactions, 3 died from other diseases, 1 died from lung metastasis, 1 died from lung infection and 1 was lost to follow-up. Conclusion: LNEC is clinically rare, the clinical manifestations are less specificity, diagnosis relies on pathological and immunohistochemical examinations, and treatment modalities and prognoses are closely related to the pathological subtypes of LNEC.
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Tumor Carcinoide , Carcinoma Neuroendocrino , Neoplasias Laríngeas , Humanos , Masculino , Femenino , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Neoplasias Laríngeas/patología , Estudios Retrospectivos , Carcinoma Neuroendocrino/diagnóstico , Carcinoma Neuroendocrino/terapia , Carcinoma Neuroendocrino/patología , Laringectomía , Tumor Carcinoide/patologíaRESUMEN
Background: The stoma can cause serious physical and psychological distress to the patient, leading to an inability to live a normal life; although it effectively improves the 5-year survival rate of patients. Objective: The purpose of this study is to explore the status of stigma and disability acceptance of patients with stoma and their influences on psychosocial adaptation. Design: A multicenter cross-sectional study. Methods: A total of 259 patients with stoma in 6 hospitals from southeast China were enrolled. And this research adhered to the STROBE guideline and approved by the Ethics Committee of Fu Jian Provincial Hospital. The ostomy adjustment inventory-20ãacceptance of disability scale and social impact scale were used to collect data. The hypothetical path model was tested using the SPSS version 22.0 software and AMOS version 26.0 software. Results: Stigma, disability acceptance and psychosocial adaptation was associated. The sense of stigma was severe (72.76 ± 12.73), the acceptance of disability was medium (179.24 ± 32.29) and the psychosocial adaptation was poor (38.06 ± 8.76). Also, the hypothesis model of this study fitted the data well (AGFI = 0.967>0.08; χ 2/df = 1.723, p = 0.08 > 0.05), and the results showed that disability acceptance positively affected psychosocial adaptation; while stigma negatively affected psychosocial adaptation, and disability acceptance mediated between stigma and psychosocial adaptation (p < 0.01). Conclusion: The stigma and disability acceptance of patients with stoma are serious problems that are closely related to their psychosocial adaptation. Medical staff should take some interventions based on different paths to reduce stoma patients' stigma and guide them to improve disability acceptance, thus to improve the level of psychosocial adaptation of patients with stoma.
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Near-infrared radiation around 1000 nm generated from the interaction of a high-density MeV electron beam, obtained by impinging an intense ultrashort laser pulse on a solid target, with a metal grating is observed experimentally. Theoretical modeling and particle-in-cell simulation suggest that the radiation is caused by the Smith-Purcell mechanism. The results here indicate that tunable terahertz radiation with tens GV/m field strength can be achieved by using appropriate grating parameters.
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It is found that stable proton acceleration from a thin foil irradiated by a linearly polarized ultraintense laser can be realized for appropriate foil thickness and laser intensity. A dual-peaked electrostatic field, originating from the oscillating and nonoscillating components of the laser ponderomotive force, is formed around the foil surfaces. This field combines radiation-pressure acceleration and target normal sheath acceleration to produce a single quasimonoenergetic ion bunch. A criterion for this mechanism to be operative is obtained and verified by two-dimensional particle-in-cell simulation. At a laser intensity of â¼5.5×10(22) W/cm(2), quasimonoenergetic GeV proton bunches are obtained with â¼100 MeV energy spread, less than 4° spatial divergence, and â¼50% energy conversion efficiency from the laser.
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Two-dimensional particle-in-cell simulations are presented of the linear and nonlinear developments of stimulated Raman scattering in two overlapping laser beams. The development of the most unstable mode in the linear stage is consistent with a previous paper [C. Z. Xiao et al., Phys. Plasmas 26, 062109 (2019)PHPAEN1070-664X10.1063/1.5096850] where SL mode (two beams share a common scattered light) is dominant in the overlapping region. This mode is enhanced with plasma density and correlation of beam polarizations. When lasers are cross-polarized, it backs to the single-beam Raman backscattering with weak intensity. Trapping-induced nonlinear frequency shift leads to the saturation of SL mode by detuning the coupling and broadening the spectrum. An interesting result that SL mode becomes stronger as the incidence angle increases is contrary to the theoretical prediction and it is a consequence of less efficient saturation in the nonlinear stage.
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OBJECTIVE: To verify that miR-92b inhibits proliferation and invasion of lung cancer by targeting EZH2. MATERIALS AND METHODS: The expression levels of miR-92b and EZH2 in human bronchial epithelial cell line BEAS-2B and human lung cancer cell line (A549, NCI-H23, NCI-H358, NCI-H1975, PC-9) were detected, and miR-92b mimic, sh-EZH2 expression vector, and plasmid blank vector (blank group) were constructed. Blank group, miR-92b mimic, miR-92b mimic+sh-EZH2 group (combined group) were set up, MTT and transwell were used to detect the proliferation and invasion ability of A549 and NCI-H23 cells, and fluorescein report verified the regulatory relationship of miR-92b to EZH2. RESULTS: The expression level of miR-92b in A549, NCI-H23, NCI-H358, NCI-H1975, and PC-9 cells was lower than that in BEAS-2B cells (p<0.05). The expression level of EZH2 was higher than that of BEAS-2B cells (p<0.05). A549 and NCI-H23 cells were selected for transfection. After that, the expression level of miR-92 in miR-92b mimic, combined group A549 and NCI-H23 cells was higher than that in blank group (p<0.05), and miR-92b mimic had no difference with joint group (p>0.05). The expression level of EZH2 in cells of miR-92b mimic, blank group A549, and NCI-H23 was lower than that of combined group (p<0.05), and miR-92b mimic was lower than that of blank group (p<0.05). After the overexpression of miR-92b, pmirGLO-EZH2-3'UT Wt luciferase activity decreased significantly (p<0.05) but had no effect on pmirGLO-EZH2-3'UTR Mut Luciferase activity (p>0.05). Cell proliferation ability and invasion ability of A549 cells and NCI-H23 cells in miR-92b mimic group were lower than those in blank group (p<0.05), while those in combined group were higher than those in miR-92b mimic group (p<0.05). CONCLUSIONS: MiR-92b inhibits proliferation and invasion of lung cancer cells through targeted inhibition of EZH2, which is a potential target for future treatment of lung cancer.
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Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Neoplasias Pulmonares/metabolismo , MicroARNs/metabolismo , Proliferación Celular , Células Cultivadas , Proteína Potenciadora del Homólogo Zeste 2/genética , Humanos , Neoplasias Pulmonares/patología , MicroARNs/genética , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
BACKGROUND: Postoperative pneumonia is the third most common complication in surgical patients. However, little is known regarding pneumonia after craniotomy, which is the most common surgical procedure in neurosurgery. AIM: To investigate the incidence of pneumonia and its association with the length of hospital stay, identify risk factors, and build a nomogram as a prediction model. METHODS: The study population was based on the American College of Surgeons' National Surgical Quality Improvement Program database from 2005 to 2017. Both multi-variate logistic regression models and linear regression models were employed. FINDINGS: The overall incidence rate of postoperative pneumonia was 3.11% in a total of 57,201 surgical procedures. Risk factors were age >55 years, male gender, low body mass index (BMI), diabetes, functional dependence, ventilator dependence, history of severe chronic obstructive pulmonary disease, hypertension, systemic sepsis, white blood cell count >12,000, emergency case, American Society of Anesthesiologists class ≥3, general anaesthesia and total surgical time >240 min. Ten featured factors were used in the nomogram (C-statistic=0.803). Postoperative pneumonia was associated with extended hospital stay. Compared with other postoperative complications, pneumonia had the second-highest impact on the extension of hospital stay (by 4.7 days). CONCLUSION: This study identified several pre-operative risk factors for postoperative pneumonia after craniotomy. Novel factors including male gender and low BMI warrant further investigation. This novel nomogram could serve as a reliable tool to evaluate the risk of postoperative pneumonia pre-operatively.
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Craneotomía/efectos adversos , Nomogramas , Neumonía/etiología , Complicaciones Posoperatorias/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Incidencia , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Factores de Riesgo , Adulto JovenRESUMEN
A Hohlraum-like configuration is proposed for realizing a simple compact source for neutrons. A laser pulse enters a tiny thin-shelled hollow-sphere target through a small opening and is self-consistently trapped in the cavity. The electrons in the inner shell-wall region are expelled by the light pressure. The resulting space-charge field compresses the local ions into a thin layer that becomes strongly heated. An inward expansion of ions into the shell cavity then occurs, resulting in the formation at the cavity center of a hot spot of ions at high density and temperature, similar to that in inertial electrostatic confinement.
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Efficient energy boost of the laser-accelerated ions is critical for their applications in biomedical and hadron research. Achiev-able energies continue to rise, with currently highest energies, allowing access to medical therapy energy windows. Here, a new regime of simultaneous acceleration of ~100 MeV protons and multi-100 MeV carbon-ions from plasma micro-channel targets is proposed by using a ~1020 W/cm2 modest intensity laser pulse. It is found that two trains of overdense electron bunches are dragged out from the micro-channel and effectively accelerated by the longitudinal electric-field excited in the plasma channel. With the optimized channel size, these "superponderomotive" energetic electrons can be focused on the front surface of the attached plastic substrate. The much intense sheath electric-field is formed on the rear side, leading to up to ~10-fold ionic energy increase compared to the simple planar geometry. The analytical prediction of the optimal channel size and ion maximum energies is derived, which shows good agreement with the particle-in-cell simulations.
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Generation of intense coherent THz radiation by obliquely incidenting an intense laser pulse on a wire target is studied using particle-in-cell simulation. The laser-accelerated fast electrons are confined and guided along the surface of the wire, which then acts like a current-carrying line antenna and under appropriate conditions can emit electromagnetic radiation in the THz regime. For a driving laser intensity â¼3×10^{18}W/cm^{2} and pulse duration â¼10 fs, a transient current above 10 KA is produced on the wire surface. The emission-cone angle of the resulting â¼0.15 mJ (â¼58 GV/m peak electric field) THz radiation is â¼30^{∘}. The conversion efficiency of laser-to-THz energy is â¼0.75%. A simple analytical model that well reproduces the simulated result is presented.
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Placode-derived general visceral afferent neurons of the nodose ganglion transmit visceral sensory information from specialized sensory endings of the vagus nerve and its branches to the nucleus of the solitary tract. These neurons are critical in relaying information such as elevations in blood pressure, changes in blood oxygenation, passage of contents through the esophagus and intestines, and distention of the heart, stomach, and lungs to the CNS for reflex maintenance of visceral functions. Multiple neurotransmitters, neuropeptides, calcium binding proteins, and other neuroactive substances are associated with neurons of the nodose ganglion. Many neurons colocalize 2 or more neuroactive substances creating the potential for complex interactions of neurochemical signals in the NTS. Neurons of the nodose ganglion also contain a variety of receptors which respond to transmitters, inflammatory mediators, and neurotrophic factors. The contents of these neurochemicals and receptors are not static as alterations in their expression are noted in response to epigenetic influences. Although not yet well understood, potential factors and mechanisms regulating neurochemical events in the nodose ganglion neurons are discussed.