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Polysaccharide-based membranes with excellent mechanical properties are highly desired. However, severe mechanical deterioration under wet conditions limits their biomedical applications. Here, inspired by the structural heterogeneity of strong yet hydrated biological materials, we propose a strategy based on heterogeneous crosslink-and-hydration (HCH) of a molecule/nano dual-scale network to fabricate polysaccharide-based nanocomposites with robust wet mechanical properties. The heterogeneity lies in that the crosslink-and-hydration occurs in the molecule-network while the stress-bearing nanofiber-network remains unaffected. As one demonstration, a membrane assembled by bacterial cellulose nanofiber-network and Ca2+-crosslinked and hydrated sodium alginate molecule-network is designed. Studies show that the crosslinked-and-hydrated molecule-network restricts water invasion and boosts stress transfer of the nanofiber-network by serving as interfibrous bridge. Overall, the molecule-network makes the membrane hydrated and flexible; the nanofiber-network as stress-bearing component provides strength and toughness. The HCH dual-scale network featuring a cooperative effect stimulates the design of advanced biomaterials applied under wet conditions such as guided bone regeneration membranes.
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Objective: This study aimed to describe and compare the epidemiological, demographic, clinical, laboratory and radiological characteristics as well as the complications, treatments, and outcomes of these patients. Methods: We retrospectively investigated clinical data of patients with C. psittaci infection (psittacosis) in eight Grade IIIA hospitals of Fujian. Metagenomic next-generation sequencing (mNGS) was used identify C. psittaci in clinical samples of all included patients. Results: A total of 74 patients (39 severe/35 non-severe) was diagnosed with psittacosis, 25 (33.8%) of whom had history of poultry exposure. Common symptoms included high fever (98% [37/74]), fatigue (52.7% [39/74]), and dyspnea (51.4% [38/74]). Common manifestations in imaging included consolidation (89.2%), pleural effusion (77.0%), and air bronchogram (66.2%). Common complications included acute respiratory distress syndrome (55.4% [41/74]), type I respiratory failure (52.7% [39/74]), acute liver injury (41.9% [31/74]), and secondary infection (27.0% [20/74]). The in-hospital mortality rate was 8.11% (6/74). Conclusion: C. psittaci infection is represents an underestimated cause of CAP. For SCAP patients with poultry and bird contact history, specimens were encouraged to be sended for mNGS test in time. C. psittaci infection can lead to severe, multiple system involvement, and several complications. mNGS facilitate timely diagnosis of C. psittaci infection.
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BACKGROUND: The associations between short- and long-term exposure to ambient fine particulate matter with an aerodynamic diameter ≤ 2.5 µm (PM2.5) and allergic symptoms in middle-aged and elderly populations remain unclear, particularly in China, where most cities have severe air pollution. METHODS: Participants (n = 10,142; age = 40-75 years) were recruited from ten regions in China from 2018 to 2021 for the Predictive Value of Inflammatory Biomarkers and Forced Expiratory Volume in 1 s (FEV1) for Chronic Obstructive Pulmonary Disease (PIFCOPD) study. Short-term (lag0 and lag0-7 day) and long-term (1-, 3- and 5-year) PM2.5 concentrations at residences were extracted from the air pollutant database known as Tracking Air Pollution (TAP) in China. Multivariate logistic regression models were used to estimate associations for short- and long-term PM2.5 exposure concentrations and long-term exposure models were additionally adjusted for short-term deviations. RESULTS: A 10 µg/m3 increase in PM2.5 on the day the allergic symptoms questionnaire was administered (lag0 day) was associated with higher odds of allergic nasal (1.09, 95% CI 1.05, 1.12) and eye symptoms (1.08, 95% CI 1.05, 1.11), worsening dyspnea caused by allergens (1.06, 95% CI 1.02, 1.10), and ≥ 2 allergic symptoms (1.07, 95% CI 1.03, 1.11), which was similar in the lag0-7 day concentrations. A 10 µg/m3 increase in the 1-year average PM2.5 concentration was associated with an increase of 23% for allergic nasal symptoms, 22% for eye symptoms, 20% for worsening dyspnea caused by allergens, and 21% for ≥ 2 allergic symptoms, similar to the 3- and 5-year average PM2.5 concentrations. These associations between long-term PM2.5 concentration and allergic symptoms were generally unchanged after adjustment for short-term deviations. CONCLUSIONS: Short- and long-term exposure to ambient PM2.5 was associated with an increased risk of allergic nasal and eye symptoms, worsening dyspnea caused by allergens, and ≥ 2 allergic symptoms. TRIAL REGISTRATION: Clinical trial ID: NCT03532893 (29 Mar 2018).
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Contaminantes Atmosféricos , Contaminación del Aire , Persona de Mediana Edad , Humanos , Anciano , Adulto , Material Particulado/efectos adversos , Material Particulado/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , China/epidemiología , Disnea , Alérgenos , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisisRESUMEN
Aim: Whether GRHL1 can be considered as a potential biomarker for screening non-small-cell lung cancer (NSCLC) is still uncertain. We aimed to investigate the value of circulating blood GRHL1 on detecting NSCLC in an older population. Materials & methods: Diagnostic models from 351 older patients with NSCLC were constructed to assess the predictive value of blood GRHL1 on distinguishing NSCLC. Results: We observed that GRHL1 (odds ratio: 3.25; 95% CI: 1.70-6.91; p < 0.001) maintained a strong relationship with an elevated rate of NSCLC after adequate clinical confounding factors were controlled for. Importantly, serum GRHL1 (area under the curve: 0.725; 95% CI: 0.708-0.863; p < 0.001) had a good predictive value. Conclusion: This is the first time that circulating GRHL1 has been shown to have good value for early detection of NSCLC in an elderly population.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Anciano , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Biomarcadores de Tumor , Curva ROC , Detección Precoz del CáncerRESUMEN
OBJECTIVES: The global coronavirus disease 2019 (COVID-19) pandemic has not been well controlled, and vaccination could be an effective way to prevent this pandemic. By accommodating attribute nonattendance (ANA) in a discrete choice experiment (DCE), this paper aimed to examine Chinese public preferences and willingness to pay (WTP) for COVID-19 vaccine attributes, especially the influence of ANA on the estimated results. METHODS: A DCE was designed with four attributes: effectiveness, protection period, adverse reactions and price. A random parameter logit model with an error component (RPL-EC) was used to analyse the heterogeneity of respondents' preferences for COVID-19 vaccine attributes. Two equality constraint latent class (ECLC) models were used to consider the influence of ANA on the estimated results in which the ECLC-homogeneity model considered only ANA and the ECLC-heterogeneity model considered both ANA and preference heterogeneity. RESULTS: Data from 1,576 samples were included in the analyses. Effectiveness had the highest relative importance, followed by adverse reactions and protection period, which were determined by the attributes and levels presented in this study. The ECLC-heterogeneity model improved the goodness of fit of the model and obtained a lower probability of ANA. In the ECLC-heterogeneity model, only a small number of respondents (29.09%) considered all attributes, and price was the most easily ignored attribute (64.23%). Compared with the RPL-EC model, the ECLC-homogeneity model obtained lower WTPs for COVID-19 vaccine attributes, and the ECLC-heterogeneity model obtained mixed WTP results. In the ECLC-heterogeneity model, preference group 1 obtained higher WTPs, and preference groups 2 and 3 obtained lower WTPs. CONCLUSIONS: The RPL-EC, ECLC-homogeneity and ECLC-heterogeneity models obtained inconsistent WTPs for COVID-19 vaccine attributes. The study found that the results of the ECLC-heterogeneity model considering both ANA and preference heterogeneity may be more plausible because ANA and low preference may be confused in the ECLC-homogeneity model and the RPL-EC model. The results showed that the probability of ANA was still high in the ECLC-heterogeneity model, although it was lower than that in the ECLC-homogeneity model. Therefore, in future research on DCE (such as the field of vaccines), ANA should be considered as an essential issue. PUBLIC CONTRIBUTION: Chinese adults from 31 provinces in mainland China participated in the study. All participants completed the COVID-19 vaccine choice questions generated through the DCE design.
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Vacunas contra la COVID-19 , COVID-19 , Adulto , COVID-19/prevención & control , Conducta de Elección , Humanos , Prioridad del Paciente , Encuestas y Cuestionarios , VacunaciónRESUMEN
BACKGROUND: Assessing the public's willingness to pay (WTP) for the coronavirus disease 2019 (COVID-19) vaccine by the contingent valuation (CV) method can provide a relevant basis for government pricing. However, the scope issue of the CV method can seriously affect the validity and reliability of the estimation results. AIM: To examine whether there are scope issues in respondents' WTP for the COVID-19 vaccine and to further verify the validity and reliability of the CV estimate results. METHOD: In this study, nine different CV double-bounded dichotomous choices (DBDC) hypothetical COVID-19 vaccine scenarios were designed using an orthogonal experimental design based on the vaccine's attributes. A total of 2450 samples from 31 provinces in Mainland China were collected to independently estimate the public's WTP in these nine scenarios with logistic, normal, log-logistic and log-normal parameter models. Based on this estimation, several external scope tests were designed to verify the validity and reliability of the CV estimate results. RESULTS: In the 20 pairs of COVID-19 vaccine scenarios, 6 pairs of scenarios were classified as negative scope issues, therefore not passing the external scope test. Of the remaining 14 pairs of scenarios, only four pairs of scenarios completely passed the external scope test, and one pair of scenarios partially passed the external scope test. Significant negative scope and scope insensitivity issues were revealed. CONCLUSION: In the context of a dynamic pandemic environment, the findings of this study reveal that the CV method may face difficulty in effectively estimating respondents' WTP for the COVID-19 vaccine. We suggest that future studies be cautious in applying the CV method to estimate the public's WTP for the COVID-19 vaccine.
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Vacunas contra la COVID-19 , COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , China , Humanos , Pandemias/prevención & control , Reproducibilidad de los Resultados , Proyectos de Investigación , Encuestas y CuestionariosRESUMEN
BACKGROUND: Survival in non-small cell lung cancer (NSCLC) remains poor. Early detection of NSCLC is of great significance to provide a chance to improve survival. AIM: We constructed predictive models to evaluate the predictive value of four tumor biomarkers by including serum human epididymis protein 4 (HE4), carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCCA), and cytokeratin 19 fragment (CY21-1) on detecting NSCLC in a Chinese elderly population. METHODS: A total of 363 patients with NSCLC and 433 subjects without cancer (healthy control group) were admitted to the respiratory department in our hospital. We assessed serum levels of these four tumor biomarkers in the two groups and then the predictive value of predictive models was evaluated. RESULTS: Serum median values of HE4 (143.3 pmol/L), CEA (4.60 ng/mL), SCCA (1.52 ng/mL), and CY21-1 (5.36 ng/mL) in patients with NSCLC were significantly higher than the healthy control group, respectively (all P<0.05). A multivariate logistic regression model showed that HE4 (OR=2.10, 95% CI=1.22-4.42, P=0.013), CEA (OR=2.30, 95% CI=1.44-4.53, P=0.004), SCCA (OR=2.20, 95% CI=1.29-4.55, P=0.011), and CY21-1 (OR=2.60, 95% CI=1.56-6.25, P<0.001) were significantly and independently associated with increased risk of NSCLC on admission after confounding factors were corrected. Importantly, the ROC curve suggested HE4 had a good value on predicting NSCLC in the Chinese elderly population. Additionally, the predictive model (CEA+SCCA+CY21-1+HE4) had better idea capability to detecting the existence of NSCLC (AUC=0.954, 95% CI=0.927-0.999, P<0.001). CONCLUSION: Our study showed that several lung cancer-related biomarkers were used to build prediction models, which has good value for early prediction of NSCLC.
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Ring-finger protein 126 (RNF126), an E3 ubiquitin ligase, plays crucial roles in various biological processes, including cell proliferation, DNA damage repair, and intracellular vesicle trafficking. Whether RNF126 is modulated by posttranslational modifications is poorly understood. Here, we show that PARP1 interacts with and poly(ADP)ribosylates RNF126, which then recruits the PAR-binding E3 ubiquitin ligase CHFR to promote ubiquitination and degradation of RNF126. Moreover, RNF126 is required for the activation of ATR-Chk1 signaling induced by either irradiation (IR) or a PARP inhibitor (PARPi), and depletion of RNF126 increases the sensitivity of triple-negative breast cancer (TNBC) cells to PARPi treatment. Our findings suggest that PARPi-mediated upregulation of RNF126 protein stability contributes to TNBC cell resistance to PARPi. Therefore, targeting the E3 ubiquitin ligase RNF126 may be a novel treatment for overcoming the resistance of TNBC cells to PARPi in clinical trials.
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Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Ftalazinas/farmacología , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Ubiquitina-Proteína Ligasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Humanos , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Células Tumorales Cultivadas , Regulación hacia ArribaRESUMEN
TLRs recognizing PAMPS play a role in local immunity and participate in implant-associated loosening. TLR-mediated signaling is primarily regulated by IL-1 receptor associated kinase-M (IRAK-M) negatively and IRAK-4 positively. Our previous studies have proved that wear particles promote endotoxin tolerance in macrophages by inducing IRAK-M. However, whether IRAK-4 is involved in inflammatory osteolysis of wear particles basically, and the specific mechanism of IRAK-4 around loosened hip implants, is still unclear. IRAK-4 was studied in the interface membranes from patients in vivo and in particle-stimulated macrophages to clarify its role. Also, IL-1ß and TNF-α levels were measured after particle and LPS stimulation in macrophages with or without IRAK-4 silenced by siRNA. Our results showed that the interface membranes around aseptic and septic loosened prosthesis expressed more IRAK-4 compared with membranes from osteoarthritic patients. IRAK-4 in macrophages increased upon particle and LPS stimulation. In the former, IL-1ß and TNF-α levels were lower compared with those of LPS stimulation, and IRAK-4 siRNA could suppress production of pro-inflammatory cytokines. These findings suggest that besides IRAK-M, IRAK-4 also plays an important role in the local inflammatory reaction and contributes to prosthesis loosening.
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Artroplastia de Reemplazo de Cadera , Vesículas Extracelulares/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Macrófagos/inmunología , Osteólisis/inmunología , Sepsis/inmunología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Interleucina-1beta/metabolismo , Masculino , Persona de Mediana Edad , Receptores de Interleucina-1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVE: Serum human epididymis protein 4 (HE4) is associated with immune and inflammatory responses. This study aimed to assess the performance of serum HE4 in the early detection of cardiovascular (CV) events in patients with chronic obstructive pulmonary disease (COPD). METHODS: Serum HE4 levels were measured in 199 patients with COPD, all of whom were prospectively followed up for a median period of 36 months (rangeâ =â 3 months-38 months). Logistic regression analysis was performed to assess the association between cardiovascular disease (CVD) history and HE4 in patients with COPD. Cox proportional hazard analysis was performed to assess the prognostic value of serum HE4 for predicting CV events. RESULTS: Serum HE4 levels were higher in patients with COPD with CV events than in those without CV events (252.6 pmol/L [186.4-366.8] vs 111.0 pmol/L [84.8-157.1]; Pâ <.001). The multivariate logistic regression model revealed that serum HE4 (odds ratioâ =â 1.639; 95% confidence interval [CI], 1.213-2.317; Ptrendâ =.009) was independently associated with CVD history after adjusting for age, sex, body mass index, current smoking status, current alcohol consumption status, admission systolic blood pressure and diastolic blood pressure, hyperlipidemia, left ventricular ejection fraction, primary diseases, and laboratory measurements in patients with COPD at baseline. The multivariate Cox proportional hazard analysis revealed that serum HE4 (hazard ratioâ =â 2.012; 95% CI, 1.773-4.469; Pâ <.001) was an independent prognostic factor for CV events in these patients. The Kaplan-Meier analysis showed that the rate of CV events was higher in patients with COPD with HE4 levels above the median (187.5 pmol/L) than in those with HE4 levels below the median. CONCLUSION: Our results showed that serum HE4 was significantly and independently associated with CVD history and had independent predictive value for CV events in patients with COPD. Serum HE4 may enable early recognition of CV complication development among patients with COPD.
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Enfermedades Cardiovasculares , Enfermedad Pulmonar Obstructiva Crónica , Enfermedades Cardiovasculares/epidemiología , Humanos , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
An increasing number of studies have indicated that red blood cell distribution width (RDW) may be a novel biomarker for the diagnosis and prognosis of various malignancies. However, to date, data on the association of RDW with non-small cell lung cancer (NSCLC) are unclear. Our present study aimed to explore the value of RDW in NSCLC patients. A total of 338 NSCLC patients, 109 small cell lung cancer (SCLC) patients, and 302 healthy participants were retrospectively analyzed between January 2016 and December 2018. In the present study, we found that RDW was significantly increased in NSCLC patients. Receiver-operating characteristic (ROC) analysis showed that the area under the ROC curve (AUC) of RDW was 0.753 in discriminating NSCLC patients from healthy participants, the optimal cut-off value of RDW was 12.95, and the specificity and sensitivity were 76.33% and 76.16%, respectively. Further analysis found that RDW can enhance the diagnostic performance of Cyfra21-1 and NSE in discriminating NSCLC patients from healthy participants or SCLC patients. Among NSCLC patients, RDW was significantly correlated with TNM stage, T stage, N stage, M stage, and Cyfra21-1, indicating that RDW may be helpful for predicting the prognosis of NSCLC patients. Our findings suggest that RDW can be used as an auxiliary marker for the diagnosis and prognosis of NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Carcinoma Pulmonar de Células Pequeñas/diagnóstico , Anciano , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Diagnóstico Diferencial , Índices de Eritrocitos , Femenino , Humanos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Sensibilidad y Especificidad , Carcinoma Pulmonar de Células Pequeñas/sangre , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Tasa de SupervivenciaRESUMEN
In this study, gemini ammonium sulfobetaine (GAS) is designed and synthesized using isophorone diisocyanate connecting the ammonium sulfobetaines (AS) to obtain a viscoelastic surfactant exhibiting better viscosification and salt resistance. AS is prepared using the monomers of erucic acid, N-dimethyl-1,3-propanediamine, and 3-chloro-2-hydroxypropanesulfonic acid sodium. The properties of GAS and its proppant suspension as well as the gel-breaking mechanisms are investigated. The critical micelle concentration of GAS is 2.1 × 10-7 mol mL-1. GAS exhibits good salt resistance, and the viscosity is considerably high under acidic conditions. At 0.5 Hz, the storage modulus G' of GAS is 60, 120, and 640 mPa when the concentration is 0.3, 0.5, and 1.0 wt%, respectively. Its proppant suspension is optimal under acidic conditions. When the pH is high, the setting velocities are clearly observed to increase. When the pH is 12, the rate of decline is more than 50% after 200 min. Some of the worm-like micelles adsorbed on the proppant surface participate in the formation of the three-dimensional network, appropriately supporting the proppant-carrying performance. When potassium permanganate is used as the gel breaker, the characterization of the GAS gel-breaking liquid indicates that the double bond is disintegrrated by the gel breaker. Upon gel breaking, the average hydrodynamic radius of the GAS gel-breaking solution decreases to 176.2 nm from 492.3 nm.
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BACKGROUND: Lung cancer is one of the most common causes of death from cancer worldwide. Smoking induces and aggravates many health problems, including vascular diseases, respiratory illnesses and cancers. Tobacco smoking constitutes the most important risk factor for lung cancer. Most people with lung cancer are still active smokers at diagnosis or frequently relapse after smoking cessation. Quitting smoking is the most effective way for smokers to reduce the risk of premature death and disability. People with lung cancer may benefit from stopping smoking. Whether smoking cessation interventions are effective for people with lung cancer and whether one method of quitting is more effective than any other has not been systematically reviewed. OBJECTIVES: To determine the effectiveness of smoking cessation programmes for people with lung cancer. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (accessed via PubMed) and Embase up to 22 December 2018. We also searched the American Society of Clinical Oncology (ASCO) Annual Meeting proceedings, the lung cancer sections of the proceedings of the ESMO Congress, the lung cancer sections of the proceedings of the European Conference of Clinical Oncology (ECCO) Congress, the World Conference on Lung Cancer proceedings, the Society for Research on Nicotine and Tobacco Annual Meeting from 2013, the Food and Drug Administration website, the European Medicine Agency for drug registration website, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal, ClinicalTrials.gov, and the metaRegister of Controlled Trials (mRCT) to 30 December 2018. We applied no restriction on language of publication. SELECTION CRITERIA: We planned to include any randomised controlled trial (RCT) of any psychosocial or pharmacological smoking cessation intervention or combinations of both, compared with no intervention, a different psychosocial or pharmacological (or both) intervention or placebo for pharmacological interventions in people with lung cancer. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the studies from the initial search for potential trials for inclusion. We planned to use standard methodological procedures expected by Cochrane. We found no trials that met the inclusion criteria. MAIN RESULTS: We identified no RCTs that met our inclusion criteria. Among the 1817 records retrieved using our search strategy, we retrieved 19 studies for further investigation. We excluded 15 trials: ten trials because we could not distinguish people with lung cancer from the other participants, or the participants were not people with lung cancer, four because they were not randomised, or RCTs. We excluded one trial because, though it was completed in 2004, no results are available. We assessed four ongoing trials for inclusion when data become available. AUTHORS' CONCLUSIONS: There were no RCTs that determined the effectiveness of any type of smoking cessation programme for people with lung cancer. There was insufficient evidence to determine whether smoking cessation interventions are effective for people with lung cancer and whether one programme is more effective than any other. People with lung cancer should be encouraged to quit smoking and offered smoking cessation interventions. However, due to the lack of RCTs, the efficacy of smoking cessation interventions for people with lung cancer cannot be evaluated and concluded. This systematic review identified a need for RCTs to explore these.
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Neoplasias Pulmonares , Cese del Hábito de Fumar , Humanos , Resultados Negativos , Fumar/efectos adversosRESUMEN
A simple, low-cost and label-free strategy for detecting lithocholic acid (LCA) was designed at the liquid crystals (LCs)/aqueous interface via competitive host-guest inclusion. In this method, sodium dodecyl sulfate (SDS) was initially adsorbed on the fluid interface and induced LCs to adopt the homeotropic ordering. Inclusion complexation of SDS and ß-cyclodextrin (ß-CD) disturbed interaction between LCs and SDS and evoked LCs to keep a tilted alignment. When injecting LCA into the mixed solution of SDS and ß-CD, SDS excluded from the cavity of ß-CD by competitive host-guest inclusion and could be re-adsorbed at the LCs/aqueous interface, resulting in the orientational transition of LCs from tilted to homeotropic state. Correspondingly, a bright-to-dark optical response was observed under polarized optical microscope (POM). The as-prepared LCs-based sensor could detect LCA as low as about 2 µM in aqueous solution. Moreover, the practicability of the approach was validated by monitoring the known amount of LCA in human urine. This work offers an appealing approach for the detection of LCA which has a great potentiality in clinical diagnosis.
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Técnicas Biosensibles , Cristales Líquidos/química , Ácido Litocólico/orina , Dodecil Sulfato de Sodio/química , beta-Ciclodextrinas/química , Adsorción , Humanos , Límite de Detección , Microscopía de Polarización , Agua/químicaRESUMEN
Fabrications and applications of luminescent films have been an interesting and important challenge within the realm of academia and industry. Herein, a novel fluorescence-based strategy for the H2O2 detection has been developed by fabrication of stabilized, thin, transparent, and luminescent films composed of europium-containing polyoxometalates (Eu-POM) and environmentally friendly chitosan (CS) via a facile solution casting approach. In comparison with pure Eu-POM, enhanced fluorescent properties are obtained from the as-prepared Eu-POM/CS films in terms of prolonged fluorescence lifetime and a remarkable fluorescent quenching effect in the presence of hydrogen peroxide (H2O2). The fluorescence intensity of Eu-POM/CS films exhibits a linear correlation in response to the H2O2 concentration over a wide range of 1.1-66 µM, with a detection limit of 0.11 µM. Furthermore, the fluorescent films display a high detection selectivity which are capable of differentiating hydrogen peroxide (H2O2) from the interfering species, such as sugars, l-amino acids, and other metabolites. All these advances towards the development of Eu-POM/CS films open up new applications for luminescent films, but most importantly, they can help in the far-reaching technological implementations of a simple, cost-effective method for the detection of H2O2 in many fields.
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A series of cationic gemini surfactants with diverse chemical structures, that is, imidazolium-based gemini surface active ionic liquids (gemini IM-SAILs) with different alkyl chain length or spacer length, viz. 1,s-bis(3-alkylimidazolium-1-yl) ethane bromide ([Cn-s-Cnim]Br2; sâ¯=â¯2, nâ¯=â¯6, 8, 10, 12, 16; nâ¯=â¯12, sâ¯=â¯2, 4, 6, 10), and quaternary ammonium-based gemini surfactants (gemini QASaa) with different symmetries, viz. 1,2-bisalkylquaternary ammonium bromide (m-2-n; mâ¯=â¯12, 14, 16, nâ¯=â¯8, 10, 12, mâ¯+â¯nâ¯=â¯24), were synthesized and utilized to decorate aqueous/liquid crystal interfaces (ALI). Initially, the optical response of the LCs changed from bright to dark after incubation with gemini IM-SAILs (except [C6-2-C6im]Br2) or gemini QASaa aqueous solutions, due to the formation of stable surfactant monolayers at the ALI. We verify that gemini IM-SAILs with shorter spacer or longer hydrophobic chains are more conducive to adsorption onto the interface, and gemini IM-SAILs form monolayers more easily than the corresponding monomers or gemini QASaa. Interestingly, a dark-to-bright shift in the optical image of the LCs subsequently occurred after the fluid interface decorated with the gemini surfactants came into contact with Bovine serum albumin (BSA), a negatively charged protein in neutral environments, whereas the optical appearance of LCs did not change upon addition of two other proteins with positive charge (viz. lysozyme and trypsin). Therefore, based on the different action mechanisms, a low-cost, label-free, and convenient LC-based sensing platform using the gemini surfactant-decorated LC interface was constructed for identification of the proteins with opposite charges.
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Studies on supramolecular gel aggregates via supramolecular interactions are very fascinating and impressive. The interactions of gelator with solvent and inorganic salt can functionalize, activate, or control the properties of supramolecular gels. A lot of work on this area has been done, but all these contributions are only at an early stage. In this work, we tuned the gel formation conditions and properties by using low-molecular-weight gelator (LMWGs), amide-functionalized imidazolium-based surfactant, viz., N-cetyl-N'-acetamido imidazolium bromide ([N-C16, N'-CONH2-Im]Br), in different solvents and with inorganic salt additives. Under chemical (Cu2+/H2O2) and physical (temperature) stimuli, gel-sol phase transition occurred in the gel formed from 2â¯wt% [N-C16, N'-CONH2-Im]Br in the solvent formamide (FM). Accompanied with increased mechanical strength of the gels, morphology alternation from initial straight stripe-shaped structures to curly belt-like textures was observed in the addition of CuBr2. From Small-angle X-ray scattering (SAXS) measurements, bilayer units with interdigitated hydrocarbon tails of the gelator were testified to appear in the gels. Comparative experiments demonstrate that the π-π interaction, H-bonding, and hydrophobic interaction between the gelator molecules are the main driving forces for the gelation. The low-cost gelator, facile preparation, and coordination-driven assembly process make the robust gel a good candidate in various applications, such as material templates and drug deliveries.
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Tripchlorolide (T4) has been shown to induce A549 lung cancer cell death predominantly by activating an autophagy pathway. However, the underlying mechanism remains unclear. Herein, we demonstrated that compared with T4 treatment alone, pretreatment with wortmannin (an inhibitor of phosphatidylinositol 3-kinase), perifosine (an inhibitor of AKT) or rapamycin (an inhibitor of mTOR) combined with a subsequent T4 treatment significantly impaired the cell viability of A549 and A549/DDP lung cancer cells. We found that either treatment scheme markedly reduced the activity of P13K and AKT. Expression of LC3II increased in parallel to the increase of the T4 concentration in both A549 and A549/DDP cells and was repressed by overexpression of AKT. The expression levels of PI3-K, PI3-P, AKT, TSC2, mTOR, p70S6K and 4E-BP1 were minimally affected by the wortmannin, perifosine, or rapamycin plus T4 treatments, but their phosphorylated products were greatly affected in A549 lung cancer cells and slightly affected in A549/DDP lung cancer cells. These results indicate that T4 induces autophagy in lung cancer cells by inhibiting the PI3K/AKT/mTOR signaling pathway. We further found that T4 decreased expression of MDR1 and improved cisplatin sensitivity of A549/DDP cells. Altogether, these results have meaningful implications for tumor therapy in the future.
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Multi-stimuli responsive materials have attracted intense attention as extensive application prospect in many fields, yet achievement of multi-stimuli responsiveness remains a challenge. Herein, we report a tri-stimuli responsive supramolecular structure fabricated by a cationic surfactant, 4-ethyl-4'-(trimethylaminohexyloxy) azobenzene bromide (ETAB), and anionic Eu-containing polyoxometalates (Eu-POM), based on an ionic self-assembly (ISA) strategy. Following different responsive mechanisms, the resultant ETAB/Eu-POM supramolecular materials are responsive to UV light, pH, and Cu(2+), respectively. The response to UV irradiation is based on the configuration change of azobenzene molecules. The response to H(+) can be attributed to the formation of a hydrogen bond W-O···H···O-H among Eu-POM, H(+), and H2O, which blocks the energy transfer pathway from O â W, while the coordination interaction between Cu(2+) and Oc (bridged oxygen of two octahedra sharing an edge in the Eu-POM molecule) causes the response to Cu(2+). The multi-stimuli responsive characteristics for the ETAB/Eu-POM supramolecular structures maybe provide a potential application in ultraviolet detection, optical storage devices, and chemical substance sensors, etc.
RESUMEN
Impacts of different substrate water potentials (SWP) on leaf gas exchange and chlorophyll fluorescence parameters of greenhouse cucumber during its post-flowering growth stage were analyzed in this study. The results demonstrated that -10 and -30 kPa were the critical values for initiating stomatal and non-stomatal limitation of drought stress, respectively. During the stage of no drought stress (-10 kPa < SWP ≤ 0 kPa), gas exchange parameters and chlorophyll fluorescence parameters were not different significantly among treatments. During the stage of stomatal limitation of drought stress (-30 kPaAsunto(s)
Clorofila/química
, Cucumis sativus/fisiología
, Hojas de la Planta/fisiología
, Transpiración de Plantas
, Agua/fisiología
, Dióxido de Carbono
, Sequías
, Fluorescencia
, Luz
, Fotosíntesis