Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-34844408

RESUMO

A membrane-lytic mechanism-based nanodrug is developed for drug-resistant tumor therapy by anchoring the small-molecule quaternary ammonium salt (QAS) on cross-linked (R)-(+)-lipoic acid nanoparticles (cLANs). The anchoring of QAS on the nanoparticle avoids the direct attack of long alkyl chains to the cell membrane under physiological conditions, while after entering tumor cells, the QAS is released from the dissociated cLANs, migrates to the phospholipid bilayer via electrostatic interaction, and destroys the cell membrane by the puncture of long alkyl chains. Since the QAS is designed to finally be hydrolyzed to amino acid betaine and food additive cetanol and the cLANs degrade to dihydrolipoic acid (DHLA, reduced form of dietary antioxidant lipoic acid in cells), the QAS@cLANs hold superior biosafety. In addition to the drug-resistant tumors, the QAS@cLANs demonstrate significant inhibition of metastatic tumors. This work provides not only a general and clinic-promising treatment for the refractory tumors but also opens a door for the medicinal use of QAS.

2.
Front Neurol ; 12: 729534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650509

RESUMO

Background: The management of patients with symptomatic non-acute intracranial artery occlusion (sNA-ICAO), which is a special subset with high morbidity and a high probability of recurrent serious ischemic events despite standard medical therapy (SMT), has been clinically challenging. A number of small-sample clinical studies have also discussed endovascular recanalization (ER) for sNA-ICAO; however, there is currently a lack of evidence from multicenter, prospective, large-sample cohort trials. The purpose of our present study was to evaluate the technical feasibility and safety of ER for sNA-ICAO. Methods: Our group is currently undertaking a multisite, non-randomized cohort, prospective registry study enrolling consecutive patients presenting with sNA-ICAO at 15 centers in China between January 1, 2020 and December 31, 2022. A cohort of patients who received SMT and a cohort of similar patients who received ER plus SMT were constructed and followed up for 2 years. The primary outcome is any stroke from enrollment to 2 years of follow-up. The secondary outcomes are all-cause mortality, mRS score, NIHSS score and cognitive function from enrollment to 30 days, 3 months, 8 months, 12 months, 18 months, and 2 years of follow-up. Descriptive statistics and linear/logistic multiple regression models will be generated. Clinical relevance will be measured as relative risk reduction, absolute risk reduction and the number needed to treat. Discussion: The management of patients with sNA-ICAO has been clinically challenging. The current protocol aims to evaluate the technical feasibility and safety of ER for sNA-ICAO. Trial Registration Number: www.ClinicalTrials.gov, identifier: NCT04864691.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34550518

RESUMO

The influence of weather and air pollution factors on hand, foot, and mouth disease (HFMD) has received widespread attention. However, most of the existing studies came from lightly polluted areas and the results were inconsistent. There was a lack of relevant evidence of heavily polluted areas. This study aims to quantify the relationship between weather factors and air pollution with HFMD in heavily polluted areas. We collected the daily number of hand, foot, and mouth disease in Shijiazhuang, China from 2014 to 2018, as well as meteorological and air pollutant data over the same period. The generalized linear model combined with the distributed lag model was used to study the effect of meteorological factors and air pollutants on the daily cases of HFMD and its hysteresis effect. We found that the dose-response relationship between temperature, PM2.5, and the risk of hand-foot-mouth disease was non-linear. Both low temperature and high temperature increased the risk of hand-foot-mouth disease. The cumulative effect of high temperature reached the maximum at 0-10 lag days, and the cumulative effect of low temperature reached the maximum at 0-3 lag days. The concentration of PM2.5 between 76 and 200 µg/m3 has a certain risk of the onset of hand, foot, and mouth disease, but the extreme PM2.5 concentration has a certain protective effect. In addition, low humidity, low wind speed, and low-O3 can increase the risk of HFMD. Risks of humidity and low concentration of O3 increased as lag days extended. In conclusion, our study found that climate factors and air pollutants exert varying degrees of impact on HFMD. Our research provided the scientific basis for establishing an early warning system so that medical staff and parents can take corresponding measures to prevent HFMD.

4.
Materials (Basel) ; 14(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576563

RESUMO

This work studied the regulation of hole concentration and mobility in p-InGaN layers grown by metalorganic chemical vapor deposition (MOCVD) under an N-rich environment. By adjusting the growth temperature, the hole concentration can be controlled between 6 × 1017/cm3 and 3 × 1019/cm3 with adjustable hole mobility from 3 to 16 cm2/V.s. These p-InGaN layers can meet different requirements of devices for hole concentration and mobility. First-principles defect calculations indicate that the p-type doping of InGaN at the N-rich limiting condition mainly originated from Mg substituting In (MgIn). In contrast with the compensation of nitrogen vacancy in p-type InGaN grown in a Ga-rich environment, the holes in p-type InGaN grown in an N-rich environment were mainly compensated by interstitial Mg (Mgi), which has very low formation energy.

5.
CNS Neurosci Ther ; 27(10): 1214-1223, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34242498

RESUMO

AIMS: To explore the safety and efficacy of normobaric oxygen (NBO) on correcting chronic cerebral ischemia (CCI) and related EEG anomalies. METHODS: This prospective randomized trial (NCT03745092) enrolled 50 cases of CCI patients, which were divided into NBO (8 L/min of oxygen supplement) group and control group (room air) randomly, and also enrolled 21 healthy volunteers. Two times of 30-min EEG recordings with the interval of 45min of NBO or room air were analyzed quantitatively. RESULTS: The CCI-mediated EEG presented with two patterns of electrical activities: high-power oscillations (high-power EEG, n = 26) and paroxysmal slow activities under the normal-power background (normal-power EEG, n = 24). The fronto-central absolute power (AP) of the beta, alpha, theta, and delta in the high-power EEG was higher than that in healthy EEG (p < 0.05). The fronto-central theta/alpha, delta/alpha and (delta + theta)/(alpha + beta) ratios in the normal-power EEG were higher than those in healthy EEG (p < 0.05). The high-power EEG in NBO group had higher fronto-central AP reduction rates than those in control group (p < 0.05). NBO remarkably reduced the fronto-central theta/alpha, delta/alpha, and (delta + theta)/(alpha + beta) ratios in the normal-power EEG (p < 0.05). CONCLUSIONS: NBO rapidly ameliorates CCI-mediated EEG anomalies, including attenuation of the abnormal high-power oscillations and the paroxysmal slow activities associated with CCI.

6.
Vascular ; : 17085381211020927, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34080448

RESUMO

OBJECTIVES: Research in the field of lower extremity vascular disease has increased in popularity over the years. To adequately characterize and validate the effectiveness of vascular interventions, in vivo experimentation in large animals is required. Thus, it is necessary to find a method to detect the shape and density of blood vessels in the lower extremities that can evaluate and verify the treatment measures' effectiveness and have high accuracy and repeatability. This study characterized factors that determined both the accuracy and overall value of digital subtraction angiography in lower limb arteriography using a canine animal model. METHODS: Six beagle dogs were anesthetized and immobilized on the motorized table. The femoral artery was accessed using an indwelling needle. A bolus of contrast agent was injected into the access site, and digital subtraction angiography with bolus chase technology was used to collect contrast images for analysis. At the end of the procedure, the anesthetized dogs were euthanized using an overdose of potassium chloride. After confirming the euthanasia of the dogs, the cadavers were taken to the experimental animal center of Xinjiang Medical University and processed by qualified institutional personnel. RESULTS: The final arteriographic images of the hind limbs from all six dogs were precise, and the branches of small vessels could be distinguished without any visible artifacts. CONCLUSIONS: These results suggested that arteriography using digital subtraction angiography could reveal the shape and density of blood vessels in canine animal models. This method has great potential to significantly improve research related to limb ischemia due to its simple and reproducible results.

7.
Mol Plant ; 14(8): 1343-1361, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34015460

RESUMO

Cereal endosperm comprises an outer aleurone and an inner starchy endosperm. Although these two tissues have the same developmental origin, they differ in morphology, cell fate, and storage product accumulation, with the mechanism largely unknown. Here, we report the identification and characterization of rice thick aleurone 1 (ta1) mutant that shows an increased number of aleurone cell layers and increased contents of nutritional factors including proteins, lipids, vitamins, dietary fibers, and micronutrients. We identified that the TA1 gene, which is expressed in embryo, aleurone, and subaleurone in caryopses, encodes a mitochondrion-targeted protein with single-stranded DNA-binding activity named OsmtSSB1. Cytological analyses revealed that the increased aleurone cell layers in ta1 originate from a developmental switch of subaleurone toward aleurone instead of starchy endosperm in the wild type. We found that TA1/OsmtSSB1 interacts with mitochondrial DNA recombinase RECA3 and DNA helicase TWINKLE, and downregulation of RECA3 or TWINKLE also leads to ta1-like phenotypes. We further showed that mutation in TA1/OsmtSSB1 causes elevated illegitimate recombinations in the mitochondrial genome, altered mitochondrial morphology, and compromised energy supply, suggesting that the OsmtSSB1-mediated mitochondrial function plays a critical role in subaleurone cell-fate determination in rice.

8.
Biomaterials ; 273: 120823, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33930738

RESUMO

Bioorthogonal prodrug activation is fascinating but suffers from staggered administration of prodrug and trigger, which would not only reduce the therapeutic effect but bring great inconvenience for clinical application. Herein, we report a new cross-linked lipoic acid nanocapsules (cLANCs) based two-component bioorthogonal nanosystem for "one-stitch" prodrug activation. Due to the reversible stability of cLANCs, the loaded prodrug and trigger cannot release in advance while can react upon arrival in the tumor tissue. Moreover, the cLANCs would be degraded into dihydrolipoic acid in tumor cells to potentiate the anticancer effect of the drug synthesized in situ. The data showed that the new bioorthogonal system held a killing effect 1.63 times higher than that of parent drug 3 against human colorectal tumor cells (HT29) and a tumor inhibitory rate 34.2% higher than that of 3 against HT29 tumor xenograft model with negligible side effects. The biodistribution study showed that the "one-stitch" prodrug activation exhibited a selective accumulation of 3 in the tumor tissue compared with free 3 group (34.2 µg vs 3.56 µg of 3/g of tissue). This two-component bioorthogonal nanosystem based on cross-linked lipoic acid nanocapsules constitutes the first example of "one-stitch" bioorthogonal prodrug activation.


Assuntos
Nanocápsulas , Neoplasias , Pró-Fármacos , Ácido Tióctico , Humanos , Nanocápsulas/uso terapêutico , Neoplasias/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Ácido Tióctico/uso terapêutico , Distribuição Tecidual
9.
Front Oncol ; 11: 620981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33842325

RESUMO

Background: It is difficult to identify pancreatic ductal adenocarcinoma (PDAC) and mass-forming chronic pancreatitis (MFCP) lesions through conventional CT or MR examination. As an innovative image analysis method, radiomics may possess potential clinical value in identifying PDAC and MFCP. To develop and validate radiomics models derived from multiparametric MRI to distinguish pancreatic ductal adenocarcinoma (PDAC) and mass-forming chronic pancreatitis (MFCP) lesions. Methods: This retrospective study included 119 patients from two independent institutions. Patients from one institution were used as the training cohort (51 patients with PDAC and 13 patients with MFCP), and patients from the other institution were used as the testing cohort (45 patients with PDAC and 10 patients with MFCP). All the patients had pathologically confirmed results, and preoperative MRI was performed. Four feature sets were extracted from T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), and the artery (A) and portal (P) phases of dynamic contrast-enhanced MRI, and the corresponding radiomics models were established. Several clinical characteristics were used to discriminate PDAC and MFCP lesions, and clinical model was established. The results of radiologists' evaluation were compared with pathology and radiomics models. Univariate analysis and the least absolute shrinkage and selection operator algorithm were performed for feature selection, and a support vector machine was used for classification. The receiver operating characteristic (ROC) curve was applied to assess the model discrimination. Results: The areas under the ROC curves (AUCs) for the T1WI, T2WI, A and, P and clinical models were 0.893, 0.911, 0.958, 0.997 and 0.516 in the primary cohort, and 0.882, 0.902, 0.920, 0.962 and 0.649 in the validation cohort, respectively. All radiomics models performed better than clinical model and radiologists' evaluation both in the training and testing cohorts by comparing the AUC of various models, all P<0.050. Good calibration was achieved. Conclusions: The radiomics models based on multiparametric MRI have the potential ability to classify PDAC and MFCP lesions.

10.
J Mater Chem B ; 9(6): 1583-1591, 2021 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-33471011

RESUMO

The nonspecific toxicity of loaded drugs and the side effect of carriers are two obstacles that hinder the clinical development of anticancer nanodrugs. Herein, we developed a new nanodrug 3-(methylthio)-propanoate camptothecin (Pro-CPT) loaded with cross-linked (R)-(+)-lipoic acid nanoparticles (Pro-CPT@cLANs). The Pro-CPT is a pH-responsive prodrug of camptothecin (CPT) that can effectively reduce the systemic toxicity of CPT caused by premature release. The cLANs are nanoparticles with structural homology to (R)-(+)-lipoic acid (LA) that hold not only LA-like biocompatibility but also LA-like anticancer activity, which may further relieve the toxicity of loaded drugs by reducing their dosages through synergistic effects and precise drug release at the tumor sites. According to in vitro data, the IC of Pro-CPT@cLANs against HT29 cells was 0.12 µM, ∼2.5 times lower than that of free Pro-CPT (0.3 µM); in vivo data showed that the tumor inhibition rate (TIR) and survival rate (SR) of Pro-CPT@cLANs against HT29 tumor-bearing nude mice were up to 85.1% and 80%, respectively, also far better than those of free CPT at the same dosage (TIR: 46%, SR: 0%). The Pro-CPT@cLANs provide a simple and efficient strategy to surmount the two obstacles in the development of nanodrugs and hold potential in clinical utility.


Assuntos
Antineoplásicos/farmacologia , Reagentes para Ligações Cruzadas/farmacologia , Nanopartículas/química , Pró-Fármacos/farmacologia , Ácido Tióctico/farmacologia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HT29 , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Tamanho da Partícula , Pró-Fármacos/química , Propriedades de Superfície , Ácido Tióctico/química
11.
Environ Res ; 195: 110310, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33098820

RESUMO

BACKGROUND: Tuberculosis (TB) is a serious public health problem in China. There is evidence to prove that meteorological factors and exposure to air pollutants have a certain impact on TB. But the evidence of this relationship is insufficient, and the conclusions are inconsistent. METHODS: Descriptive epidemiological methods were used to describe the distribution characteristics of TB in Shijiazhuang in the past five years. Through the generalized linear regression model (GLM) and the generalized additive model (GAM), the risk factors that affect the incidence of TB are screened. A combination of GLM and distribution lag nonlinear model (DLNM) was used to evaluate the lag effect of environmental factors on the TB. Results were tested for robustness by sensitivity analysis. RESULTS: The incidence of TB in Shijiazhuang showed a downward trend year by year, with seasonality and periodicity. Every 10 µg/m3 of PM10 changes, the RR distribution is bimodal. The first peak of RR occurs on the second day of lag (RR = 1.00166, 95% CI: 1.00023, 1.00390); the second risk period starts from 13th day of lag and peaks on15th day (RR = 1.00209, 95% CI: 1.00076, 1.00341), both of which are statistically significant. The cumulative effect of increasing 10 µg/m3 showed a similar bimodal distribution. Time zones where the RR makes sense are days 4-6 and 13-20. RR peaked on the 18th day (RR = 1.02239, 95% CI: 1.00623, 1.03882). The RR has a linear relationship with the concentration. Under the same concentration, the RR peaks within 15-20 days. CONCLUSION: TB in Shijiazhuang City showed a downward trend year by year, with obvious seasonal fluctuations. The air pollutant PM10 increases the risk of TB. The development of TB has a short-term lag and cumulative lag effects. We should focus on protecting susceptible people from TB in spring and autumn, and strengthen the monitoring and emission management of PM10 in the atmosphere.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Tuberculose , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologia , Cidades , Humanos , Conceitos Meteorológicos , Material Particulado/análise , Tuberculose/epidemiologia
12.
Adv Healthc Mater ; 10(3): e2001430, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33274859

RESUMO

Herein, a new nanodrug of azobenzene-functionalized interfacial cross-linked reverse micelles (AICRM) with 5-fluorouracil loading (5-FU@AICRM) is reported. Upon irradiation with 530 nm light in water, the surface azobenzenes of the nanoparticles change from polar cis-conformation to nonpolar trans-conformation, resulting in the aggregation of 5-FU@AICRM within minutes. Simultaneously, the conformation change unlocks hydrophilic 5-FU with a strong water immigration propensity, allowing them to spray out from the AICRM quickly. This fast release ensures a thorough release of the drug, before the aggregates are internalized by adjacent cells, making it possible to achieve deep tissue penetration. A study of in vivo anticancer activity in A549 tumor-bearing nude mice shows that the tumor inhibition rate (TIR) of 5-FU@AICRM is up to ≈86.2%, 31.6% higher than that of group without green light irradiation and 20.7% higher than that of carmofur (CF, a hydrophobic analog of 5-FU)-loaded AICRM (CF@AICRM), in which CF is released slowly under light irradiation because of its hydrophobicity. Fast drug release upon nanodrug aggregation provides a good solution for balancing the contradiction of "aggregation and penetration" in tumor treatment with nanodrugs.


Assuntos
Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Fluoruracila , Camundongos , Camundongos Nus , Micelas
13.
J Mater Chem B ; 9(1): 159-169, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33226389

RESUMO

Self-adhering hydrogels are promising materials to be employed as wound dressings, because they can be used for wound healing without the necessity of additional stitching. However, micro-organisms can easily adhere to these hydrogels as well, which usually causes wound infections. Therefore, adhesive hydrogels are often combined with antibiotics. However, this introduces a risk of drug resistance, cytotoxicity and poor cell affinity. Consequently, recently, there has been great interest in developing non-antibiotic, antibacterial adhesive hydrogels. In this article, we present a simple one-pot synthesis procedure to prepare self-adhesive hydrogels composed of poly(acrylamide) (PAM), naturally derived chitosan (CS) and tannic acid/ferric ion chelates (TA@Fe3+). TA@Fe3+ enables self-catalysis of the polymerization reaction. In addition, due to its near infrared (NIR) photothermal responsiveness, TA@Fe3+ allows for eliminating the bacterial activity with up to 91.6% and 94.7% effectivity against Escherichia coli and Staphylococcus aureus, respectively. Mechanical and adhesion testing shows that the hydrogels are tough as well as flexible and will adhere repeatedly to many types of biological tissues, which can be attributed to the combination of physical and chemical bonding between TA@Fe3+ and PAM and CS, respectively. Moreover, in vitro and in vivo tests indicate that the NIR photothermally active hydrogel can effectively prevent bacterial infection and accelerate tissue regeneration, which demonstrates that these hydrogels are promising functional materials for wound healing applications.


Assuntos
Antibacterianos/síntese química , Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico , Células 3T3 , Animais , Antibacterianos/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Catálise , Células Cultivadas , Hidrogéis/administração & dosagem , Camundongos , Ratos , Ratos Sprague-Dawley , Cicatrização/fisiologia , Infecção dos Ferimentos/patologia
14.
Huan Jing Ke Xue ; 41(9): 4141-4149, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124296

RESUMO

Municipal wastewater methanogenesis is one of the ways to utilize municipal wastewater resources.In this study, a biofilter used to treat actual municipal wastewater was employed to investigate the methanogenesis in a pilot-scale reactor. The method of rapid start-up, the influence of temperature on the reactor performance, and the changes in the microbial structure were investigated in the pilot-scale study. The rapid start-up of the biofilter reactor was achieved by the combination of intermittent and continuous operations. The effluent concentration of SCOD was 60 mg ·L-1at the stable operation stage. The biofilter was operated steadily at a temperature higher than 14℃, the accumulation of volatile fatty acids (VFA) was low, and the effluent concentrations of SCOD and TCOD were 69 mg ·L-1and 90 mg ·L-1, respectively. In addition, the metabolism of hydrolysis and methanogenesis tended to balance off under such conditions. However, the abundance of microorganisms that can hydrolyze organic matter and produce methane decreased. The abundance of Peptostreptococcaceae increased even the temperature was lower than 10℃, which typically increases VFA production. Therefore, the concentrations of effluent VFA and TCOD increased, but methane production decreased. The effluent concentration of SCOD was relatively stable. The microbial abundance and diversity were the richest at 19℃ in the reactor. The acetolactic methanogens were the dominant methanogens at low temperatures. The anaerobic biological filter for the treatment of urban sewage starts quickly and can resist the impact of continuous temperature reduction. Moreover, it does not need backwashing after running for nine months, and it is not easily clogged.Therefore,the functions of biological contact oxidation and filtration retention of the biological filter can be more fully utilized.


Assuntos
Microbiota , Águas Residuárias , Anaerobiose , Reatores Biológicos , Metano , Esgotos , Temperatura , Eliminação de Resíduos Líquidos
15.
J Am Chem Soc ; 142(45): 19308-19315, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33108173

RESUMO

Developing efficient single-atom catalysts (SACs) for nitrogen fixation is of great importance while remaining a great challenge. The lack of an effective strategy to control the polarization electric field of SACs limits their activity and selectivity. Here, using first-principles calculations, we report that a single transition metal (TM) atom sandwiched between hexagonal boron nitride (h-BN) and graphene sheets (namely, BN/TM/G) acts as an efficient SAC for the electrochemical nitrogen reduction reaction (NRR). These sandwich structures realize stable and tunable interfacial polarization fields that enable the TM atom to donate electrons to a neighboring B atom as the active site. As a result, the partially occupied pz orbital of a B atom can form B-to-N π-back bonding with the antibonding state of N2, thus weakening the N≡N bond. The not-strong-not-weak electric field on the h-BN surface further promotes N2 adsorption and activation. The NRR catalytic activity of the BN/TM/G system is highly correlated with the degree of positively polarized charges on the TM atom. In particular, BN/Ti/G and BN/V/G are identified as promising NRR catalysts with high stability, offering excellent energy efficiency and suppression of the competing hydrogen evolution reaction.

16.
J Agric Food Chem ; 68(40): 11114-11120, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32936618

RESUMO

Phosphorite is generally used in the manufacture of phosphate fertilizer and plays a vital role in the development of agricultural and food production. Nonetheless, how to obtain phosphorite concentrates efficiently and sustainably has become an urgent problem. In this study, a newly designed trisiloxane surfactant, N-(2-Aminoethyl)-3-aminopropyltrisiloxane (AATS), has been prepared and utilized as an emerging collector for reverse flotation of phosphorite ore. Its collecting ability was compared with the conventional surfactant 1-dodecamine (DDA). In the collector concentration tests, AATS with lower concentrations showed stronger collecting ability for quartz. In the pH tests, AATS always performed better than DDA in the acidic or alkaline condition. In bench-scale flotation experiments, the P2O5 recovery of phosphorite concentrates with 150 g/t AATS was 10.77% higher than that with 300 g/t DDA, which proved that AATS can be applied to the sustainable production of phosphorite concentrates. For a 4000 t/d phosphorite ore processing plant, the profit could be increased 7,014,702.07 USD every year by using AATS as the collector. Therefore, this work provides a promising approach to enhance the production efficiency of phosphate fertilizer and to promote the sustainable development of agriculture.


Assuntos
Fertilizantes/análise , Minerais/química , Fosfatos/química , Siloxanas/química , Tensoativos/química , Quartzo/química , Tensoativos/síntese química
17.
Nano Lett ; 20(9): 6548-6555, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32787159

RESUMO

Artificial organelles (AOs) are typical microcompartments with intracellular biocatalytic activity aimed to replace missing or lost cellular functions. Currently, liposomes or polymersomes are popular microcompartments to build AOs by embedding channel proteins in their hydrophobic domain and entrapping natural enzymes in their cavity. Herein, a new microcompartment is established by using monolayer cross-linked zwitterionic vesicles (cZVs) with a carboxylic acid saturated cavity. The monolayer structure endows the cZVs with intrinsic permeability; the cavity supplies the cZVs ability of in situ synthesis of artificial enzymes, and the pH-dependent charge-change property makes it possible to overcome the biological barriers. Typically, nanozymes of CeO2 and Pt NPs were synthesized in the cZVs to mimic peroxisome. In vitro experiments confirmed that the resulting artificial peroxisome (AP) could resist protein adsorption, endocytose efficiently, and escape from the lysosome. In vivo experiments demonstrated that the APs held a good therapeutic effect in ROS-induced ear-inflammation.


Assuntos
Células Artificiais , Biocatálise , Interações Hidrofóbicas e Hidrofílicas , Organelas , Permeabilidade , Proteínas
18.
Nat Commun ; 11(1): 2752, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487992

RESUMO

Nonlinear optical switches that reversibly convert between on/off states by thermal stimuli are promising for applications in the fields of photoelectronics and photonics. Currently one main drawback for practical application lies in the control of their switch temperature, especially for the temperature range near room temperature. By mixed melting treatment, here we describe an alloy-like nonlinear optical switch with tunable switch temperature via a dual solid solution approach within the coordination polymer system. We initially prepare a coordination polymer (i-PrNHMe2)[Cd(SCN)3], which functions as a high-contrast thermoresponsive nonlinear optical switch originating from a phase transition at around 328 K. Furthermore, by taking advantage of a synergistic dual solid solution effect, the melt mixing of it with its analogue (MeNHEt2)[Cd(SCN)3], which features an unequal anionic chain templated by an isomeric ammonium, can afford coordination polymer solid solutions with switch temperatures that are tunable in a range of 273-328 K merely by varying the component ratio.

19.
Biomed Res Int ; 2020: 3208391, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32461977

RESUMO

Background: Trastuzumab has been introduced a decade ago and demonstrated improvement in the prognosis in patients with human epidermal growth factor receptor 2- (HER2-) positive (+) breast carcinoma (BC). This study is aimed at evaluating the efficacy of epirubicin/cyclophosphamide with weekly paclitaxel-trastuzumab as neoadjuvant chemotherapies in HER2+ BC patients. Methods: A total of 234 HER2+ BC patients were given neoadjuvant chemotherapy (NAC) between 2010 and 2016. The primary endpoints were pathologic complete response (pCR) and disease-free survival (DFS). Univariate and multivariate analyses of clinical and pathological factors associated with pCR and DFS were conducted. Results: The pCR (30.4% vs. 14.8%; P = 0.004) and DFS (P = 0.036) showed significant differences between patients administered with neoadjuvant trastuzumab therapy and those who did not. Multivariate logistic regression analysis showed that neoadjuvant trastuzumab treatment was regarded as an independent predictor of pCR. Patients with pCR had prolonged DFS (P = 0.025). In patients who did not achieve pCR (non-pCR), those who received trastuzumab had more prolonged DFS (P = 0.046). The luminal B/HER2+ subtypes had prolonged DFS when compared with nonluminal B/HER2+ subtypes (P = 0.010). The luminal B/HER2+ subgroup also showed improved DFS in non-pCR patients (P = 0.010). In the subgroup of non-pCR, the luminal B/HER2+ subgroup administered with trastuzumab showed no superior DFS (P = 0.168). However, a positive result was observed in patients without trastuzumab (P = 0.039). Multivariate analysis showed cT stage (P = 0.006) and tumor grade (P = 0.041), considering them as significant prognostic factors of DFS. Conclusions: HER2+ BC patients showed improvement in pCR and DFS after neoadjuvant trastuzumab treatment. Patients without pCR had prolonged DFS after trastuzumab maintenance. Although the prognosis of luminal B/HER2+ BC showed favorable outcomes in the non-pCR subgroup, those receiving trastuzumab showed no survival advantage.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Ciclofosfamida/uso terapêutico , Epirubicina/uso terapêutico , Receptores ErbB/metabolismo , Terapia Neoadjuvante/métodos , Paclitaxel/uso terapêutico , Trastuzumab/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Prognóstico , Receptor ErbB-2 , Trastuzumab/administração & dosagem
20.
J Gastrointest Oncol ; 11(2): 329-336, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32399274

RESUMO

Background: Preoperative staging of pancreatic cancer determines the choice of treatment. Magnetic resonance imaging (MRI) plays an important role in preoperative staging of pancreatic cancer. The American Joint Committee on Cancer (AJCC) TNM staging system was revised to its 8th version in 2016, there has been no report correlating the 8th edition of the AJCC TNM staging with preoperative MRI examinations and pathological findings. The purpose of our study is to determine the staging accuracy and evaluate the resectability by using MRI about pancreatic cancer compared with intraoperative or pathological findings according to the 8th edition of the AJCC TNM staging system. Methods: One hundred thirty-two patients with a pathological diagnosis of pancreatic cancer who underwent preoperative MRI were identified. The clinical data, MRI findings and pathological findings were analyzed. Preoperative MRI staging and resectability evaluation were compared with pathological findings. The accuracy of MRI for preoperative T and N staging was evaluated, and the sensitivity, specificity and accuracy of MRI in evaluating the resectability were assessed. All the staging and resectability assessments were according to the 8th edition of the AJCC TNM staging system. Results: Analysis showed that the accuracy of MRI for evaluation of the T and N stages was 82.6% (109/132) and 74.2% (98/132), respectively. The sensitivity and specificity of MRI in assessing the resectability were 94.2% and 71.4%, respectively. Integrating the 8th edition of the AJCC TNM stage, no significant differences were identified between the preoperative MRI and pathological results for the staging of pancreatic cancer (P=0.805). Conclusions: MRI is highly accurate for T staging and moderately accurate for N staging. MRI provides important preoperative evaluation of the stage and resectability of pancreatic cancer based on the 8th edition of the AJCC TNM staging system.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...