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In this work, a numerical method is proposed to predict the electrokinetic phenomena and combined with an experimental study of the surface charge density (ρs) and zeta potential (ζ) behavior is investigated for borosilicate immersed in KCl and NaCl electrolytes, and for imogolite immersed in KCl, CaCl2, and MgCl2 electrolytes. Simulations and experiments of the electrokinetic flows with electrolyte solutions were performed to accurately determine the electric double layer (EDL), ζ, and ρs at various electrolyte concentrations and pH. The zeta potential was experimentally determined and numerically predicted by solving the coupled governing equations of mass, species, momentum, and electrical field iteratively. Our numerical prediction shows that ζ for borosilicate develops strong nonlinear behavior with the ion concentration following a power-law. Likewise, the ρs obeys a nonlinear behavior, decreasing as the concentration increases. Moreover, for imogolite, both ζ and the ρs behave nonlinearly with the pH. The EDL for borosilicate and imogolite becomes thinner as the electrolyte concentration and pH increase; this behavior is caused by increased ρs, resulting in the higher attraction of the free charges. The reported nonlinear behavior describes more accurately the interaction of the nanoparticle surface charge with the electrolytes and its effect on the electrolyte transport properties.

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PURPOSE: To explore the regulatory effect of let-7a-5p/TGFBR1/Smad3 on the proliferation activity of cervical cancer cells. METHODS: The difference in let-7a-5p expression between normal people and patients with cervical cancer was detected by miREIA assay. The differences of let-7a-5p expression between cervical cancer cell line C33a and adjacent normal epithelial cell line HUCEC were determined by qRT-PCR. RESULTS: miREIA result showed that let-7a-5p concentrations were 178.5 ± 24.3 µg/L in healthy individuals and 106.1 ± 14.8 µg/L in cervical cancer patients (P = 0.0002). qRT-PCR showed that let-7a-5p in cervical cancer tissue (0.57 ± 0.03) was lower than that in adjacent normal tissue (0.84 ± 0.04, P = 0.0107). Compared with normal cervical epithelial cells (HUCEC), the expression of let-7a-5p was lower in cervical cancer cells (C33a, Hela, P = 0.0001). The results of CCK-8 and EDU detection showed that activation of let-7a-5p inhibited the proliferation of C33a (P = 0.00130, P << 0.0001) and Hela (P = 0.00254, P = 0.0066) cells. According to the analysis using Starbase V2.0 online database, let-7a-5p could target TGFßR1 in cervical cancer cell lines, and the let-7a-5p mimic reduces the mRNA expression level of TGFßR1 in cervical cancer cell C33a (P = 0.0067). Western blot results showed that TGFBR1 expression significantly decreased in cervical cancer cells after let-7a-5p mimic treatment (P = 0.0048) and significantly increased after let-7a-5p mimic inhibitor treatment (P = 0.0003). CONCLUSIONS: let-7a-5p represents the independent novel anti-oncogenes in cervical cancer, which can regulate TGF-ß1/TGFBR1/pSmad3 cell pathway and interfere with the proliferation of cervical cancer cells. Therefore, let-7a-5p can serve as a novel potential therapeutic target for the treatment of cervical cancer.

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OBJECTIVE: Bedside lung ultrasound (LUS) is a noninvasive, readily available imaging modality that can complement clinical evaluation. The Bedside Lung Ultrasound in Emergency (BLUE) protocol has demonstrated a high diagnostic accuracy in patients with acute respiratory failure (ARF). Recently, bedside LUS has been added to the medical training program of our ICU. The aim of this study was to investigate the accuracy of LUS based on the BLUE protocol, when performed by physicians who are not ultrasound experts, to guide the diagnosis of ARF. METHODS: Over a one-year period, all spontaneously breathing adult patients consecutively admitted to the ICU for ARF were prospectively included. After training, 4 non-ultrasound experts performed LUS within 20 minutes of patient admission. They were blinded to patient medical history. LUS diagnosis was compared with the final clinical diagnosis made by the ICU team before patients were discharged from the ICU (gold standard). RESULTS: Thirty-seven patients were included in the analysis (mean age, 73.2 ± 14.7 years; APACHE II, 19.2 ± 7.3). LUS diagnosis had a good agreement with the final diagnosis in 84% of patients (overall kappa, 0.81). The most common etiologies for ARF were pneumonia (n = 17) and hemodynamic lung edema (n = 15). The sensitivity and specificity of LUS as measured against the final diagnosis were, respectively, 88% and 90% for pneumonia and 86% and 87% for hemodynamic lung edema. CONCLUSIONS: LUS based on the BLUE protocol was reproducible by physicians who are not ultrasound experts and accurate for the diagnosis of pneumonia and hemodynamic lung edema.

OBJETIVO: O ultrassom pulmonar (USP) à beira do leito é uma técnica de imagem não invasiva e prontamente disponível que pode complementar a avaliação clínica. O protocolo Bedside Lung Ultrasound in Emergency (BLUE, ultrassom pulmonar à beira do leito em situações de emergência) demonstrou elevado rendimento diagnóstico em pacientes com insuficiência respiratória aguda (IRpA). Recentemente, um programa de treinamento em USP à beira do leito foi implementado na nossa UTI. O objetivo deste estudo foi avaliar a acurácia do USP baseado no protocolo BLUE, quando realizado por médicos com habilidades básicas em ultrassonografia, para orientar o diagnóstico de IRpA. MÉTODOS: Ao longo de um ano, todos os pacientes adultos consecutivos respirando espontaneamente admitidos na UTI por IRpA foram prospectivamente inclusos. Após treinamento, 4 operadores com habilidades básicas em ultrassonografia realizaram o USP em até 20 minutos após a admissão na UTI, cegados para a história do paciente. Os diagnósticos do USP foram comparados aos diagnósticos da equipe assistente ao final da internação na UTI (padrão-ouro). RESULTADOS: Foram inclusos na análise 37 pacientes (média etária: 73,2 ± 14,7 anos; APACHE II: 19,2 ± 7,3). O diagnóstico do USP demonstrou concordância com o diagnóstico final em 84% dos casos (kappa total: 0,81). As causas mais comuns de IRpA foram pneumonia (n = 17) e edema pulmonar cardiogênico (n = 15). A sensibilidade e a especificidade do USP comparado ao diagnóstico final foram de 88% e 90% para pneumonia e de 86% e 87% para edema pulmonar cardiogênico, respectivamente. CONCLUSÕES: O USP baseado no protocolo BLUE foi reproduzível por médicos com habilidades básicas em ultrassonografia e acurado para o diagnóstico de pneumonia e de edema pulmonar cardiogênico.

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Objective: Bedside lung ultrasound (LUS) is a noninvasive, readily available imaging modality that can complement clinical evaluation. The Bedside Lung Ultrasound in Emergency (BLUE) protocol has demonstrated a high diagnostic accuracy in patients with acute respiratory failure (ARF). Recently, bedside LUS has been added to the medical training program of our ICU. The aim of this study was to investigate the accuracy of LUS based on the BLUE protocol, when performed by physicians who are not ultrasound experts, to guide the diagnosis of ARF. Methods: Over a one-year period, all spontaneously breathing adult patients consecutively admitted to the ICU for ARF were prospectively included. After training, 4 non-ultrasound experts performed LUS within 20 minutes of patient admission. They were blinded to patient medical history. LUS diagnosis was compared with the final clinical diagnosis made by the ICU team before patients were discharged from the ICU (gold standard). Results: Thirty-seven patients were included in the analysis (mean age, 73.2 ± 14.7 years; APACHE II, 19.2 ± 7.3). LUS diagnosis had a good agreement with the final diagnosis in 84% of patients (overall kappa, 0.81). The most common etiologies for ARF were pneumonia (n = 17) and hemodynamic lung edema (n = 15). The sensitivity and specificity of LUS as measured against the final diagnosis were, respectively, 88% and 90% for pneumonia and 86% and 87% for hemodynamic lung edema. Conclusions: LUS based on the BLUE protocol was reproducible by physicians who are not ultrasound experts and accurate for the diagnosis of pneumonia and hemodynamic lung edema. .

Objetivo: O ultrassom pulmonar (USP) à beira do leito é uma técnica de imagem não invasiva e prontamente disponível que pode complementar a avaliação clínica. O protocolo Bedside Lung Ultrasound in Emergency (BLUE, ultrassom pulmonar à beira do leito em situações de emergência) demonstrou elevado rendimento diagnóstico em pacientes com insuficiência respiratória aguda (IRpA). Recentemente, um programa de treinamento em USP à beira do leito foi implementado na nossa UTI. O objetivo deste estudo foi avaliar a acurácia do USP baseado no protocolo BLUE, quando realizado por médicos com habilidades básicas em ultrassonografia, para orientar o diagnóstico de IRpA. Métodos: Ao longo de um ano, todos os pacientes adultos consecutivos respirando espontaneamente admitidos na UTI por IRpA foram prospectivamente inclusos. Após treinamento, 4 operadores com habilidades básicas em ultrassonografia realizaram o USP em até 20 minutos após a admissão na UTI, cegados para a história do paciente. Os diagnósticos do USP foram comparados aos diagnósticos da equipe assistente ao final da internação na UTI (padrão-ouro). Resultados: Foram inclusos na análise 37 pacientes (média etária: 73,2 ± 14,7 anos; APACHE II: 19,2 ± 7,3). O diagnóstico do USP demonstrou concordância com o diagnóstico final em 84% dos casos (kappa total: 0,81). As causas mais comuns de IRpA foram pneumonia (n = 17) e edema pulmonar cardiogênico (n = 15). A sensibilidade e a especificidade do USP comparado ao diagnóstico final foram de 88% e 90% para pneumonia e de 86% e 87% para edema pulmonar cardiogênico, respectivamente. Conclusões: O USP baseado no protocolo BLUE foi reproduzível por médicos com habilidades básicas em ultrassonografia e acurado para o diagnóstico de pneumonia e de edema pulmonar cardiogênico. .

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BACKGROUND: In acute lung injury positive end-expiratory pressure (PEEP) and recruitment maneuver are proposed to optimize arterial oxygenation. The aim of the study was to evaluate the impact of such a strategy on lung histological inflammation and hyperinflation in pigs with acid aspiration-induced lung injury. METHODS: Forty-seven pigs were randomly allocated in seven groups: (1) controls spontaneously breathing; (2) without lung injury, PEEP 5 cm H2O; (3) without lung injury, PEEP titration; (4) without lung injury, PEEP titration + recruitment maneuver; (5) with lung injury, PEEP 5 cm H2O; (6) with lung injury, PEEP titration; and (7) with lung injury, PEEP titration + recruitment maneuver. Acute lung injury was induced by intratracheal instillation of hydrochloric acid. PEEP titration was performed by incremental and decremental PEEP from 5 to 20 cm H2O for optimizing arterial oxygenation. Three recruitment maneuvers (pressure of 40 cm H2O maintained for 20 s) were applied to the assigned groups at each PEEP level. Proportion of lung inflammation, hemorrhage, edema, and alveolar wall disruption were recorded on each histological field. Mean alveolar area was measured in the aerated lung regions. RESULTS: Acid aspiration increased mean alveolar area and produced alveolar wall disruption, lung edema, alveolar hemorrhage, and lung inflammation. PEEP titration significantly improved arterial oxygenation but simultaneously increased lung inflammation in juxta-diaphragmatic lung regions. Recruitment maneuver during PEEP titration did not induce additional increase in lung inflammation and alveolar hyperinflation. CONCLUSION: In a porcine model of acid aspiration-induced lung injury, PEEP titration aimed at optimizing arterial oxygenation, substantially increased lung inflammation. Recruitment maneuvers further improved arterial oxygenation without additional effects on inflammation and hyperinflation.

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OBJECTIVE: To compare the efficiency of an Aeroneb Pro vibrating plate and an Atomisor MegaHertz ultrasonic nebulizer for providing ceftazidime distal lung deposition. DESIGN: In vitro experiments. One gram of cetazidime was nebulized in respiratory circuits and mass median aerodynamic diameter of particles generated by ultrasonic and vibrating plate nebulizers was compared using a laser velocimeter. In vivo experiments. Lung tissue concentrations and extrapulmonary depositions were measured in ten anesthetized ventilated piglets with healthy lungs that received 1 g of ceftazidime by nebulization with either an ultrasonic (n = 5), or a vibrating plate (n = 5) nebulizer. SETTING: A two-bed Experimental Intensive Care Unit of a University School of Medicine. INTERVENTION: Following sacrifice, 5 subpleural specimens were sampled in dependent and nondependent lung regions for measuring ceftazidime lung tissue concentrations by high-performance liquid chromatography. MEASUREMENTS AND RESULTS: Mass median aerodynamic diameters generated by both nebulizers were similar with more than 95% of the particles between 0.5 and 5 microm. Lung tissue concentrations were 553 +/- 123 [95% confidence interval: 514-638] microg g(-1) using ultrasonic nebulizer, and 452 +/- 172 [95% confidence interval: 376-528] microg g(-1) using vibrating plate nebulizers (NS). Extrapulmonary depositions were, respectively, of 38 +/- 5% (ultrasonic) and 34 +/- 4% (vibrating plate) (NS). CONCLUSIONS: Vibrating plate nebulizer is comparable to ultrasonic nebulizers for ceftazidime nebulization. It may represent a new attractive technology for inhaled antibiotic therapy.

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BACKGROUND: In spontaneously breathing cardiac patients, pulmonary artery pressure (PAP) can be accurately estimated from the transthoracic Doppler study of pulmonary artery and tricuspid regurgitation blood flows. In critically ill patients on mechanical ventilation for acute lung injury, the interposition of gas between the probe and the heart renders the transthoracic approach problematic. This study was aimed at determining whether the transesophageal approach could offer an alternative. METHODS: Fifty-one consecutive sedated and ventilated patients with severe hypoxemia (arterial oxygen tension/fraction of inspired oxygen < 300) were prospectively studied. Mean PAP measured from the pulmonary artery catheter was compared with several indices characterizing pulmonary artery blood flow assessed using transesophageal echocardiography: preejection time, acceleration time, ejection duration, preejection time on ejection duration ratio, and acceleration time on ejection duration ratio. In a subgroup of 20 patients, systolic PAP measured from the pulmonary artery catheter immediately before withdrawal was compared with Doppler study of regurgitation tricuspid flow performed immediately after pulmonary artery catheter withdrawal using either the transthoracic or the transesophageal approach. RESULTS: Weak and clinically irrelevant correlations were found between mean PAP and indices of pulmonary artery flow. A statistically significant and clinically relevant correlation was found between systolic PAP and regurgitation tricuspid flow. In 3 patients (14%), pulmonary artery pressure could not be assessed echocardiographically. CONCLUSIONS: In hypoxemic patients on mechanical ventilation, mean PAP cannot be reliably estimated from indices characterizing pulmonary artery blood flow. Systolic PAP can be estimated from regurgitation tricuspid flow using either transthoracic or transesophageal approach.

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