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1.
Phys Rev Lett ; 132(11): 116201, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563913

RESUMO

Intriguing topological polar structures in oxide nanofilms have drawn growing attention owing to their immense potential applications in nanoscale electronic devices. Here, we report a novel route to mechanically manipulate polar structures via flexoelectricity in wrinkled thin films. Our results present a flexoelectric polar transition from a nonpolar state to uniaxial polar stripes, biaxial meronlike or antimeronlike polar structures, and polar labyrinths by varying wrinkle morphologies. The evolution mechanisms and the outstanding mechanical tunability of these flexoelectric polar patterns were investigated theoretically and numerically. This strategy based on flexoelectricity for generating nontrivial polar structures will no longer rely on the superlattice structure and can be widely applicable to all centrosymmetric or noncentrosymmetric materials, providing a broader range of material and structure candidates for polar topologies.

2.
Am J Respir Crit Care Med ; 208(4): 435-441, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37315325

RESUMO

Rationale: The CAPTURE tool (Chronic Obstructive Pulmonary Disease [COPD] Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk) was developed to identify patients with undiagnosed COPD with an FEV1 <60% predicted or risk of exacerbation as treatment criteria. Objectives: To test the ability of CAPTURE to identify patients requiring treatment because of symptoms or risk of exacerbation or hospitalization. Methods: Data were from COMPASS (Clinical, Radiological and Biological Factors Associated with Disease Progression, Phenotypes and Endotypes of COPD in China), a prospective study of COPD, chronic bronchitis without airflow limitation (postbronchodilator FEV1/FVC ratio ≥0.70), and healthy never-smokers. CAPTURE was tested as questions alone and with peak expiratory flow measurement. Sensitivity, specificity, and positive and negative predicted values (PPV and NPV) were calculated for COPD Assessment Test (CAT) scores ⩾10 versus <10, modified Medical Research Council (mMRC) scores ⩾2 versus <2, and at least one moderate exacerbation or hospitalization in the previous year versus none. Measurements and Main Results: Patients with COPD (n = 1,696) had a mean age of 65 ± 7.5 years, and 90% were male, with a postbronchodilator FEV1 of 66.5 ± 20.1% predicted. Control participants (n = 307) had a mean age of 60.2 ± 7.0 years, and 65% were male, with an FEV1/FVC ratio of 0.78 ± 0.04. CAPTURE using peak expiratory flow showed the best combination of sensitivity and specificity. Sensitivity and specificity were 68.5% and 64.0%, respectively, to detect a CAT score ⩾10; 85.6% and 61.0% to detect an mMRC score ⩾2; 63.5% and 55.6% to detect at least one moderate exacerbation; and 70.2% and 59.4% to detect at least one hospitalization. PPVs ranged from 15.6% (moderate exacerbations) to 47.8% (CAT score). NPVs ranged from 80.8% (CAT score) to 95.6% (mMRC score). Conclusions: CAPTURE has good sensitivity to identify patients with COPD who may require treatment because of increased symptoms or risk of exacerbations or hospitalization, including those with an FEV1 >60% predicted. High NPV values show that CAPTURE can also exclude those who may not require treatment. Clinical trial registered with www.clinicaltrials.gov (NCT04853225).


Assuntos
Doença Pulmonar Obstrutiva Crônica , Masculino , Feminino , Humanos , Estudos Prospectivos , Volume Expiratório Forçado , Pulmão , Sensibilidade e Especificidade , Progressão da Doença
3.
Dermatol Ther ; 35(4): e15303, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34984792

RESUMO

Chronic spontaneous urticaria (CSU) is characterized by the spontaneous development of wheals, itching, and/or angioedema, for ≥6 weeks. In China, non-sedating H1-antihistamines (H1AH) are the recommended first-line treatment, with escalation up to 4× the standard dose in symptomatic patients to achieve control. Treatment options for Chinese patients who remain symptomatic on H1AH treatment are limited. This 20-week randomized, double blind, placebo-controlled, parallel-group study investigated the efficacy and safety of omalizumab as an add-on therapy for the treatment of patients with CSU who remained symptomatic despite H1AH treatment in China. Adult patients (N = 418) diagnosed with refractory CSU for ≥6 months were randomized (2:2:1) to receive omalizumab 300 mg (OMA300), omalizumab 150 mg (OMA150) or placebo, subcutaneously, every 4 weeks. Primary outcome was change from baseline to week 12 in weekly itch severity score (ISS7). Safety was assessed by rates of adverse events (AEs). Demographic and disease characteristics at baseline were comparable across treatment groups. At week 12, statistically significant greater decreases from baseline were observed in ISS7 with OMA300 (least square mean difference [LSM]: -4.23; 95% confidence interval [CI]: -5.70, -2.77; p < 0.001) and OMA150 (LSM: -3.79; 95% CI: -5.24, -2.33; p < 0.001) versus placebo. Incidence of treatment-emergent AEs over 20 weeks was slightly higher with OMA300 (71.3%) compared to OMA150 and placebo groups (64.7% and 63.9%, respectively). The incidences of serious AEs were balanced between groups. This study demonstrated the efficacy and safety of omalizumab in Chinese adult patients with CSU who remained symptomatic despite H1AH therapy.


Assuntos
Antialérgicos , Urticária Crônica , Urticária , Adulto , Antialérgicos/efeitos adversos , Doença Crônica , Urticária Crônica/diagnóstico , Urticária Crônica/tratamento farmacológico , Antagonistas dos Receptores Histamínicos H1 , Humanos , Omalizumab/efeitos adversos , Resultado do Tratamento , Urticária/induzido quimicamente , Urticária/diagnóstico , Urticária/tratamento farmacológico
4.
Sensors (Basel) ; 22(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365833

RESUMO

In the field of ultra high accuracy inertial measurement unit (IMU), pendulous integrating gyroscopic accelerometer (PIGA) has become a research hot spot due to its high-end performance. However, PIGA is sensitive to angular velocity, and the calibration process of PIGA-based IMU will be very complicated, which makes online self-calibration difficult to implement. To solve the above problems, we proposed an online self-calibration method utilizing angular velocity observation. The main contributions of this study are twofold: (1) An error analysis of PIGA is conducted in this paper, and the error model has also been simplified to suit the self-calibration model. (2) An improved online self-calibration method utilizing angular observation based on a simplified PIGA error model is proposed in this study. Experimental results show that the self-calibration method proposed in this study can improve the PIGA online calibration accuracy effectively (with the accuracy within 0.02 m/s/pulse), which can improve the dynamic accuracy of the PIGA.

5.
J Immunol ; 203(7): 1961-1972, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31451675

RESUMO

Human mesenchymal stem cell (MSC) extracellular vesicles (EV) can reduce the severity of bacterial pneumonia, but little is known about the mechanisms underlying their antimicrobial activity. In the current study, we found that bacterial clearance induced by MSC EV in Escherichia coli pneumonia in C57BL/6 mice was associated with high levels of leukotriene (LT) B4 in the injured alveolus. More importantly, the antimicrobial effect of MSC EV was abrogated by cotreatment with a LTB4 BLT1 antagonist. To determine the role of MSC EV on LT metabolism, we measured the effect of MSC EV on a known ATP-binding cassette transporter, multidrug resistance-associated protein 1 (MRP1), and found that MSC EV suppressed MRP1 mRNA, protein, and pump function in LPS-stimulated Raw264.7 cells in vitro. The synthesis of LTB4 and LTC4 from LTA4 are competitive, and MRP1 is the efflux pump for LTC4 Inhibition of MRP1 will increase LTB4 production. In addition, administration of a nonspecific MRP1 inhibitor (MK-571) reduced LTC4 and subsequently increased LTB4 levels in C57BL/6 mice with acute lung injury, increasing overall antimicrobial activity. We previously found that the biological effects of MSC EV were through the transfer of its content, such as mRNA, microRNA, and proteins, to target cells. In the current study, miR-145 knockdown abolished the effect of MSC EV on the inhibition of MRP1 in vitro and the antimicrobial effect in vivo. In summary, MSC EV suppressed MRP1 activity through transfer of miR-145, thereby resulting in enhanced LTB4 production and antimicrobial activity through LTB4/BLT1 signaling.


Assuntos
Lesão Pulmonar Aguda , Infecções por Escherichia coli , Escherichia coli/imunologia , Vesículas Extracelulares , Células-Tronco Mesenquimais/imunologia , Pneumonia Bacteriana , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/terapia , Animais , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/terapia , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/patologia , Vesículas Extracelulares/transplante , Humanos , Leucotrieno B4/imunologia , Leucotrieno C4/imunologia , Pulmão/imunologia , Pulmão/patologia , Masculino , Células-Tronco Mesenquimais/patologia , Camundongos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/imunologia , Pneumonia Bacteriana/imunologia , Pneumonia Bacteriana/patologia , Pneumonia Bacteriana/terapia , Propionatos/farmacologia , Quinolinas/farmacologia , Células RAW 264.7
6.
Thorax ; 74(1): 43-50, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30076187

RESUMO

BACKGROUND: We previously reported that microvesicles (MVs) released by human mesenchymal stem cells (MSC) were as effective as the cells themselves in both Escherichia coli lipopolysaccharide and live bacteria-induced acute lung injury (ALI) mice models. However, it remained unclear whether the biological effect of MSC MV can be applied to human ALI. METHODS: In the current study, we tested the therapeutic effects of MSC MVs in a well-established ex vivo perfused human model of bacterial pneumonia. Using human donor lungs not used for transplantation, we instilled E. coli bacteria intrabronchially and, 1 hour later, administered MSC MVs into the perfusate as therapy. RESULTS: After 6 hours, instillation of E. coli bacteria caused influx of inflammatory cells, which resulted in significant inflammation, lung protein permeability and pulmonary oedema formation. Administration of MSC MV significantly increased alveolar fluid clearance and reduced protein permeability and numerically lowered the bacterial load in the injured alveolus. The beneficial effect on bacterial killing was more pronounced with pretreatment of MSCs with a Toll-like receptor 3 agonist, polyinosinic:polycytidylic acid (Poly (I:C)), prior to the isolation of MVs. Isolated human alveolar macrophages had increased antimicrobial activity with MSC MV treatment in vitro as well. Although oxygenation and lung compliance levels were similar between injury and treatment groups, administration of MSC MVs numerically decreased median pulmonary artery pressure at 6 hours. CONCLUSIONS: In summary, MSC MVs increased alveolar fluid clearance and reduced lung protein permeability, and pretreatment with Poly (I:C) enhanced the antimicrobial activity of MVs in an ex vivo perfused human lung with severe bacteria pneumonia.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , Lesão Pulmonar Aguda/terapia , Terapia Baseada em Transplante de Células e Tecidos , Micropartículas Derivadas de Células , Infecções por Escherichia coli/complicações , Células-Tronco Mesenquimais , Pneumonia Bacteriana/complicações , Proteínas/metabolismo , Alvéolos Pulmonares/metabolismo , Lesão Pulmonar Aguda/microbiologia , Lesão Pulmonar Aguda/patologia , Adulto , Idoso , Pressão Arterial , Carga Bacteriana , Micropartículas Derivadas de Células/efeitos dos fármacos , Feminino , Humanos , Indutores de Interferon/farmacologia , Contagem de Leucócitos , Complacência Pulmonar , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Pessoa de Meia-Idade , Neutrófilos , Técnicas de Cultura de Órgãos , Oxigênio/metabolismo , Permeabilidade , Poli I-C/farmacologia , Alvéolos Pulmonares/microbiologia , Alvéolos Pulmonares/patologia , Artéria Pulmonar , Edema Pulmonar/microbiologia , Edema Pulmonar/terapia , Receptor 3 Toll-Like/agonistas , Fator de Necrose Tumoral alfa/metabolismo
7.
Crit Care Med ; 45(7): e727-e733, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28441237

RESUMO

OBJECTIVE: To evaluate the effectiveness of noninvasive ventilation in patients with acute hypoxemic nonhypercapnic respiratory failure unrelated to exacerbation of chronic obstructive pulmonary disease and cardiogenic pulmonary edema. DATA SOURCES: PubMed, EMBASE, Cochrane library, Web of Science, and bibliographies of articles were retrieved inception until June 2016. STUDY SELECTION: Randomized controlled trials comparing application of noninvasive ventilation with standard oxygen therapy in adults with acute hypoxemic nonhypercapnic respiratory failure were included. Chronic obstructive pulmonary disease exacerbation and cardiogenic pulmonary edema patients were excluded. The primary outcome was intubation rate; ICU mortality and hospital mortality were secondary outcomes. DATA EXTRACTION: Demographic variables, noninvasive ventilation application, and outcomes were retrieved. Internal validity was assessed using the risk of bias tool. The strength of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation methodology. DATA SYNTHESIS: Eleven studies (1,480 patients) met the inclusion criteria and were analyzed by using a random effects model. Compared with standard oxygen therapy, the pooled effect showed that noninvasive ventilation significantly reduced intubation rate with a summary risk ratio of 0.59 (95% CI, 0.44-0.79; p = 0.0004). Furthermore, hospital mortality was also significantly reduced (risk ratio, 0.46; 95% CI, 0.24-0.87; p = 0.02). Subgroup meta-analysis showed that the application of bilevel positive support ventilation (bilevel positive airway pressure) was associated with a reduction in ICU mortality (p = 0.007). Helmet noninvasive ventilation could reduce hospital mortality (p = 0.0004), whereas face/nasal mask noninvasive ventilation could not. CONCLUSIONS: Noninvasive ventilation decreased endotracheal intubation rates and hospital mortality in acute hypoxemia nonhypercapnic respiratory failure excluding chronic obstructive pulmonary disease exacerbation and cardiogenic pulmonary edema patients. There is no sufficient scientific evidence to recommend bilevel positive airway pressure or helmet due to the limited number of trials available. Large rigorous randomized trials are needed to answer these questions definitely.


Assuntos
Ventilação não Invasiva/métodos , Insuficiência Respiratória/terapia , Doença Aguda , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Intubação Intratraqueal/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Stem Cells ; 34(12): 2943-2955, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27350036

RESUMO

Activation of mast cells participates in the chronic inflammation associated with cerebral arteries in intracranial aneurysm formation and rupture. Several studies have shown that the anti-inflammatory effect of mesenchymal stem cells (MSCs) is beneficial for the treatment of aneurysms. However, some long-term safety concerns exist regarding stem cell-based therapy for clinical use. We investigated the therapeutic potential of microvesicles (MVs) derived from human MSCs, anuclear membrane bound fragments with reparative properties, in preventing the rupture of intracranial aneurysm in mice, particularly in the effect of MVs on mast cell activation. Intracranial aneurysm was induced in C57BL/6 mice by the combination of systemic hypertension and intrathecal elastase injection. Intravenous administration of MSC-derived MVs on day 6 and day 9 after aneurysm induction significantly reduced the aneurysmal rupture rate, which was associated with reduced number of activated mast cells in the brain. A23187-induced activation of both primary cultures of murine mast cells and a human mast cell line, LAD2, was suppressed by MVs treatment, leading to a decrease in cytokine release and tryptase and chymase activities. Upregulation of prostaglandin E2 (PGE2) production and E-prostanoid 4 (EP4) receptor expression were also observed on mast cells with MVs treatment. Administration of an EP4 antagonist with the MVs eliminated the protective effect of MVs against the aneurysmal rupture in vivo. Human MSC-derived MVs prevented the rupture of intracranial aneurysm, in part due to their anti-inflammatory effect on mast cells, which was mediated by PGE2 production and EP4 activation. Stem Cells 2016;34:2943-2955.


Assuntos
Aneurisma Roto/prevenção & controle , Micropartículas Derivadas de Células/metabolismo , Dinoprostona/metabolismo , Aneurisma Intracraniano/prevenção & controle , Mastócitos/patologia , Células-Tronco Mesenquimais/metabolismo , Administração Intravenosa , Aneurisma Roto/patologia , Aneurisma Roto/terapia , Animais , Anti-Inflamatórios/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Calcimicina/farmacologia , Micropartículas Derivadas de Células/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Humanos , Imunomodulação/efeitos dos fármacos , Terapia de Imunossupressão , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/terapia , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo
9.
Am J Respir Crit Care Med ; 192(3): 324-36, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26067592

RESUMO

RATIONALE: Microvesicles (MVs) are anuclear fragments of cells released from the endosomal compartment or shed from surface membranes. We and other investigators demonstrated that MVs released by mesenchymal stem cells (MSCs) were as effective as the cells themselves in inflammatory injuries, such as after endotoxin-induced acute lung injury. However, the therapeutic effects of MVs in an infectious model of acute lung injury remain unknown. OBJECTIVES: We investigated the effects of human MSC MVs on lung inflammation, protein permeability, bacterial clearance, and survival after severe bacterial pneumonia. METHODS: We tested the effects of MVs derived from human MSCs on Escherichia coli pneumonia in mice. We also studied the interactions between MVs and human monocytes and human alveolar epithelial type 2 cells. MEASUREMENTS AND MAIN RESULTS: Administration of MVs derived from human MSCs improved survival in part through keratinocyte growth factor secretion and decreased the influx of inflammatory cells, cytokines, protein, and bacteria in mice injured with bacterial pneumonia. In primary cultures of human monocytes or alveolar type 2 cells, the uptake of MVs was mediated by CD44 receptors, which were essential for the therapeutic effects. MVs enhanced monocyte phagocytosis of bacteria while decreasing inflammatory cytokine secretion and increased intracellular ATP levels in injured alveolar epithelial type 2 cells. Prestimulation of MSCs with a toll-like receptor 3 agonist further enhanced the therapeutic effects of the released MVs. CONCLUSIONS: MVs derived from human MSCs were as effective as the parent stem cells in severe bacterial pneumonia.


Assuntos
Lesão Pulmonar Aguda/terapia , Micropartículas Derivadas de Células/transplante , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais , Pneumonia Bacteriana/terapia , Lesão Pulmonar Aguda/microbiologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Mediators Inflamm ; 2016: 2347938, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313398

RESUMO

Recently, mesenchymal stem cells (MSC) have been proved to be beneficial in acute respiratory distress syndrome (ARDS). Vascular endothelial growth factor (VEGF) is an important angiogenesis factor that MSC release. However, the precise role of VEGF-expressing character of MSC in the MSC treatment for ARDS remains obscure. Here, we firstly knocked down the gene VEGF in MSC (MSC-ShVEGF) with lentiviral transduction. Then we injected the MSC-ShVEGF to rats with lipopolysaccharide-induced acute lung injury (ALI) via the tail vein. Data showed that MSC transplantation significantly increased VEGF levels in the lung, reduced lung permeability, protected lung endothelium from apoptosis, facilitated VE-cadherin recovery, controlled inflammation, and attenuated lung injury. However, VEGF gene knockdown in MSC led to relatively insufficient VEGF expression in the injured lung and significantly diminished the therapeutic effects of MSC on ALI, suggesting an important role of VEGF-expressing behavior of MSC in the maintenance of VEGF in the lung and the MSC treatment for ALI. Hence, we conclude that MSC restores the lung permeability and attenuates lung injury in rats with ALI in part by maintaining a "sufficient" VEGF level in the lung and the VEGF-expressing character of MSC plays a positive role in the therapeutic effects of MSC on ARDS.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/terapia , Animais , Células Cultivadas , Edema/metabolismo , Edema/patologia , Imunofluorescência , Marcação In Situ das Extremidades Cortadas , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/toxicidade , Pulmão/metabolismo , Pulmão/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Crescimento do Endotélio Vascular/genética
11.
J Cell Physiol ; 230(3): 691-701, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25200929

RESUMO

Angiotensin (Ang) II plays an important role in the process of endothelial dysfunction in acute lung injury (ALI) and is degraded by angiotensin-converting enzyme2 (ACE2). However, treatments that target ACE2 to injured endothelium and promote endothelial repair of ALI are lacking. Mesenchymal stem cells (MSCs) are capable of homing to the injured site and delivering a protective gene. Our study aimed to evaluate the effects of genetically modified MSCs, which overexpress the ACE2 protein in a sustained manner via a lentiviral vector, on Ang II production in endothelium and in vitro repair of lipopolysaccharide (LPS)-induced endothelial injury. We found that the efficiency of lentiviral vector transduction of MSCs was as high as 97.8% and was well maintained over 30 passages. MSCs modified with ACE2 showed a sustained high expression of ACE2 mRNA and protein. The modified MSCs secreted soluble ACE2 protein into the culture medium, which reduced the concentration of Ang II and increased the production of Ang 1-7. MSCs modified with ACE2 were more effective at restoring endothelial function than were unmodified MSCs, as shown by the enhanced survival of endothelial cells; the downregulated production of inflammatory mediators, including ICAM-1, VCAM-1, TNF-α, and IL-6; reduced paracellular permeability; and increased expression of VE-cadherin. These data demonstrate that MSCs modified to overexpress the ACE2 gene can produce biologically active ACE2 protein over a sustained period of time and have an enhanced ability to promote endothelial repair after LPS challenge. These results encourage further testing of the beneficial effects of ACE2-modified MSCs in an ALI animal model.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Angiotensina II/metabolismo , Células-Tronco Mesenquimais/metabolismo , Peptidil Dipeptidase A/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/patologia , Angiotensina I/genética , Angiotensina II/genética , Enzima de Conversão de Angiotensina 2 , Animais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Terapia Genética , Células HEK293 , Humanos , Lipopolissacarídeos/toxicidade , Células-Tronco Mesenquimais/citologia , Camundongos , Fragmentos de Peptídeos/genética , Peptidil Dipeptidase A/genética , Sistema Renina-Angiotensina
12.
Crit Care ; 19: 130, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25887027

RESUMO

INTRODUCTION: The effect of mean arterial pressure titration to a higher level on microcirculation in septic shock patients with previous hypertension remains unknown. Our goal is to assess the effect of mean arterial pressure titration to a higher level on microcirculation in hypertensive septic shock patients. METHODS: This is a single-center, open-label study. Hypertensive patients with septic shock for less than 24 hours after adequate fluid resuscitation and requiring norepinephrine to maintain a mean arterial pressure of 65 mmHg were enrolled. Mean arterial pressure was then titrated by norepinephrine from 65 mmHg to the normal level of the patient. In addition to hemodynamic variables, sublingual microcirculation was evaluated by sidestream dark field imaging. RESULTS: Nineteen patients were enrolled in the study. Increasing mean arterial pressure from 65 mmHg to normal levels was associated with increased central venous pressure (from 11 ± 4 to 13 ± 4 mmHg, P = 0.002), cardiac output (from 5.4 ± 1.4 to 6.4 ± 2.1 l/minute, P = 0.001), and central venous oxygen saturation (from 81 ± 7 to 83 ± 7%, P = 0.001). There were significant increases in small perfused vessel density (from 10.96 ± 2.98 to 11.99 ± 2.55 vessels/mm(2), P = 0.009), proportion of small perfused vessels (from 85 ± 18 to 92 ± 14%, P = 0.002), and small microvascular flow index (from 2.45 ± 0.61 to 2.80 ± 0.68, P = 0.009) when compared with a mean arterial pressure of 65 mmHg. CONCLUSIONS: Increasing mean arterial pressure from 65 mmHg to normal levels is associated with improved microcirculation in hypertensive septic shock patients. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01443494; registered 28 September 2011.


Assuntos
Pressão Arterial/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Microcirculação/efeitos dos fármacos , Choque Séptico/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Feminino , Hidratação , Hemodinâmica/efeitos dos fármacos , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Soalho Bucal/irrigação sanguínea , Norepinefrina/administração & dosagem , Norepinefrina/farmacologia , Estudos Prospectivos , Respiração Artificial/métodos , Choque Séptico/fisiopatologia , Vasoconstritores/administração & dosagem , Vasoconstritores/farmacologia
13.
Zhonghua Nei Ke Za Zhi ; 53(1): 48-54, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24674729

RESUMO

OBJECTIVE: To evaluate the effect of sucralfate and acid-suppressive drugs on preventing ventilator-associated pneumonia (VAP) in mechanically ventilated patients. METHODS: All randomized controlled trials (RCTs), which studied the effect of sucralfate and acid-suppressive drugs on the incidence of VAP in mechanically ventilated patients, were searched from PubMed, Embase and the Cochrane Library during January 1966 to March 2013 via manual and computer retrieval. All related data were extracted. Meta analysis was conducted using the statistical software RevMan 5.2 and the quality of the RCTs was strictly evaluated with the methods recommended by the Cochrane Collaboration. RESULTS: A total of 15 RCTs involving 1315 patients in the sucralfate group and 1568 patients in the acid-suppressive drug group were included in this study. The incidence of VAP was significantly reduced in the sucralfate group (RR = 0.81, 95%CI 0.7-0.95, P = 0.008), while no difference was found between the two groups in the incidence of stress-related gastrointestinal bleeding (RR = 0.96, 95%CI 0.59-1.58, P = 0.88). No statistical difference was found in the days on ventilator, duration of ICU stay and ICU mortality in the two groups (all P values > 0.05). CONCLUSION: In patients with mechanical ventilation, sucralfate could decrease the incidence of VAP, while has no such effect on the stress-related gastrointestinal bleeding, the days on ventilator, duration of ICU stay and ICU mortality.


Assuntos
Antiácidos/uso terapêutico , Hemorragia Gastrointestinal/prevenção & controle , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Sucralfato/uso terapêutico , Úlcera/prevenção & controle , Antiácidos/farmacologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sucralfato/farmacologia
14.
Nanomaterials (Basel) ; 14(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38668209

RESUMO

Lenses have been a cornerstone of optical systems for centuries; however, they are inherently limited by the laws of physics, particularly in terms of size and weight. Because of their characteristic light weight, small size, and subwavelength modulation, metalenses have the potential to miniaturize and integrate imaging systems. However, metalenses still face the problem that chromatic aberration affects the clarity and accuracy of images. A high-quality image system based on the end-to-end joint optimization of a neural network and an achromatic metalens is demonstrated in this paper. In the multi-scale encoder-decoder network, both the phase characteristics of the metalens and the hyperparameters of the neural network are optimized to obtain high-resolution images. The average peak-signal-to-noise ratio (PSNR) and average structure similarity (SSIM) of the recovered images reach 28.53 and 0.83. This method enables full-color and high-performance imaging in the visible band. Our approach holds promise for a wide range of applications, including medical imaging, remote sensing, and consumer electronics.

15.
ERJ Open Res ; 10(3)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38770009

RESUMO

Background: In China, the prevalence of severe asthma with eosinophilic phenotype is rising, yet treatment options are limited. Mepolizumab is the first targeted biologic therapy for eosinophilic-driven disease in China. This study (clinicaltrials.gov identifier NCT03562195) evaluated efficacy and safety of mepolizumab in Chinese patients with severe asthma. Methods: The phase III, multicentre, randomised, placebo-controlled, double-blind, parallel-group study enrolled patients aged ≥12 years with severe asthma, with two or more exacerbations in the previous year, and on inhaled corticosteroids plus at least one controller medication. Following a 1-4-week run-in, patients were randomised 1:1 to mepolizumab 100 mg or placebo subcutaneously every 4 weeks for 52 weeks. The primary end-point was annualised rate of clinically significant exacerbations (CSEs) through week 52. Secondary end-points were time to first CSE, frequency of CSEs requiring hospitalisation/emergency department visits or hospitalisation over 52 weeks, mean change in St George's Respiratory Questionnaire (SGRQ) total score and pre-bronchodilator forced expiratory volume in 1 s (FEV1) at week 52; safety was evaluated. Results: The modified intention-to-treat population included 300 patients. At week 52 with mepolizumab versus placebo, annualised rate of CSEs was 65% lower (0.45 versus 1.31 events per year; rate ratio 0.35, 95% CI 0.24-0.50; p<0.001); time to first CSE longer (hazard ratio 0.38, 95% CI 0.26-0.56; p<0.001) and number of CSEs requiring hospitalisation/emergency department visit lower (rate ratio 0.30, 95% CI 0.12-0.77; p=0.012). From baseline to week 52, SGRQ score improved (p=0.001) and pre-bronchodilator FEV1 increased (p=0.006). Incidence of adverse events was similar between treatment groups. Conclusion: Mepolizumab provided clinical benefits to patients with severe asthma in China and showed a favourable benefit-risk profile.

16.
Nanomaterials (Basel) ; 12(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36500921

RESUMO

Metalenses composed of a large number of subwavelength nanostructures provide the possibility for the miniaturization and integration of the optical system. Broadband polarization-insensitive achromatic metalenses in the visible light spectrum have attracted researchers because of their wide applications in optical integrated imaging. This paper proposes a polarization-insensitive achromatic metalens operating over a continuous bandwidth from 470 nm to 700 nm. The silicon nitride nanopillars of 488 nm and 632.8 nm are interleaved by Fresnel zone spatial multiplexing method, and the particle swarm algorithm is used to optimize the phase compensation. The maximum time-bandwidth product in the phase library is 17.63. The designed focal length can be maintained in the visible light range from 470 nm to 700 nm. The average focusing efficiency reaches 31.71%. The metalens can achieve broadband achromatization using only one shape of nanopillar, which is simple in design and easy to fabricate. The proposed metalens is expected to play an important role in microscopic imaging, cameras, and other fields.

17.
Stem Cell Res Ther ; 13(1): 496, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209115

RESUMO

BACKGROUND: Microvesicles (MVs) derived from human bone marrow mesenchymal stem cell (MSC) were demonstrated to restore lung protein permeability and attenuate acute lung injury. In our previous study, we found that MSC MV increased sphingosine-1-phosphate (S1P) kinase1 mRNA levels in injured human lung microvascular endothelial cells (HLMVEC) significantly. However, the role of S1P signaling in MSC MV to restore lung protein permeability is unknown. METHODS: In this study, we hypothesized that MSC MV might restore lung permeability in part through increasing intracellular S1P signaling pathway in injured HLMVEC independent of S1P receptors. We used the transwell co-culture system to study the effect of MSC MV on protein permeability of Lipopolysaccharide (LPS) damaged HLMVEC. RESULTS: Our results showed that LPS significantly increased the permeability of HLMVEC to FITC-dextran (70 kDa) within 24 h. MSC MV restores this permeability and, to a large extent, prevents the cytoskeleton protein F-actin from recombining into "actin stress fibers," and restores the positions of tight junctions and adhesion junctions in the damaged HLMVEC. This therapeutic effect of MSC MV was related to the increase in the S1P level in injured HLMVEC and was not eliminated when adding the antagonist of S1P receptor, suggesting that MSC MV to restore lung permeability was independent of S1P receptors on HLMVEC. Laser confocal further observed that Ca2+ mobilization and Rac1 activation in LPS injured HLMVEC were increased in parallel with the increase in intracellular S1P level after MSC MV treatment. CONCLUSIONS: In short, MSC MV partially restored protein permeability across HLMVEC through the intracellular S1P signaling pathway independent of S1P receptor-1.


Assuntos
Lipopolissacarídeos , Células-Tronco Mesenquimais , Receptores de Esfingosina-1-Fosfato/metabolismo , Actinas/metabolismo , Permeabilidade Capilar , Células Endoteliais/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Lisofosfolipídeos , Células-Tronco Mesenquimais/metabolismo , Permeabilidade , RNA Mensageiro/metabolismo , Transdução de Sinais , Esfingosina/análogos & derivados
18.
Front Public Health ; 9: 720512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616706

RESUMO

Ensuring the well-being of persons with disabilities (PWDs) is a priority in the public sector during the coronavirus disease 2019 (COVID-19) pandemic. To contain this unprecedented public crisis in China, a set of nationwide anti-epidemic discourse systems centered on war metaphors has guided the epidemic's prevention and control. While the public is immersed in the joy brought by the stage victory, most ignore the situation of the disadvantaged PWDs. Accordingly, this study adopts and presents a qualitative research method to explore the impact of war metaphors on PWDs. The results showed that while there was some formal and informal support for PWDs during this period, they were increasingly marginalized. Owing to the lack of a disability lens and institutional exclusion, PWDs were placed on the margins of the epidemic prevention and control system like outsiders. Affected by pragmatism under war metaphors, PWDs are regarded as non-contributory or inefficient persons; therefore, they are not prioritized and are thus placed into a state of being voiceless and invisible. This research can provide inspiration for improving public services for PWDs in the context of COVID-19.


Assuntos
COVID-19 , Pessoas com Deficiência , China/epidemiologia , Humanos , Metáfora , Pandemias/prevenção & controle , SARS-CoV-2
19.
Pediatr Dermatol ; 26(3): 360-2, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19706112

RESUMO

Normolipemic papuloeruptive xanthomatosis is a very rare skin disorder. We report a child with yellowish papular eruptions on the face that rapidly merged into confluent plaques. Serum lipid profiles showed normolipemia. A diagnosis of normolipemic papuloeruptive xanthomatosis with no associated systemic disorders was made. The skin lesions involuted spontaneously during follow-up.


Assuntos
Lipídeo A/sangue , Dermatopatias/patologia , Xantomatose/patologia , Feminino , Humanos , Lactente , Pele/patologia , Dermatopatias/sangue , Xantomatose/sangue
20.
Opt Express ; 16(25): 20968-73, 2008 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-19065236

RESUMO

This study explores two-dimensional binary sub-wavelength diffractive lenses (BSDLs) for implementing long focal depth and high transverse resolution based on the rigorous electromagnetic theory and the finite-difference time-domain method. Focusing performances, such as the actual focal depth, the ratio between the focal depth of the designed BSDL and the focal depth of the conventional sub-wavelength lens and the spot size of the central lobe at the actual focal plane, for different f-numbers, have been studied in the case of TE incidence polarization wave. The rigorous numerical results indicate that the designed BSDLs indeed have long focal depth and high transverse resolution by modulating the binary sub-wavelength characteristic sizes. Because BSDLs have the ability for monolithic integration and can require only single step fabrication, the investigations may provide useful information for BSDLs' application in micro-optical systems.


Assuntos
Desenho Assistido por Computador , Lentes , Modelos Teóricos , Refratometria/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
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