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1.
Adv Mater ; : e2004481, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33015905

RESUMO

Simultaneous photodynamic therapy (PDT) and photothermal therapy (PTT) can reduce the risks of drug leakage, body burden, and preparation complexity in traditional combination PDT/PTT. Here, a versatile nanoporphyrin (Pp18-lipos) self-assembled from lipid-purpurin 18 conjugates (Pp18-lipids) and pure lipids is presented. The as-prepared Pp18-lipos with 2 mol% Pp18-lipids can perform effective PDT and fluorescence imaging. The Pp18-lipos with 65 mol% Pp18 can perform potent PTT and photoacoustic imaging. The chelation of Mn2+ endows the Pp18-lipids-Mn2+ a high T1 -weighted magnetic resonance imaging contrast. Notably, pretreatment of low-dose PDT facilitates the endocytosis and tumor accumulation of Pp18-lipos, thus achieving synergistic PDT/PTT. Upon exposure to a single 705 nm-laser, the combination of PDT/PTT achieves a significantly higher tumor growth inhibition rate than PDT or PTT alone. In addition, it is found that the synergistic PDT/PTT triggers more potent anti-tumor immune response including tumor infiltration of immune cells and release of related cytokines.

2.
Nanotechnology ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33120370

RESUMO

Ag/TiO2 nanostructure arrays were constructed on fluorine-doped tin oxide (FTO) via a controllable hydrothermal route and a magnetron sputtering method with a variety of TiO2 arrays decorated by Ag nanoparticles. Effects of different TiO2 arrays on the microstructure, composition, and optical properties of the samples were revealed. As surface enhanced Raman scattering (SERS) active substrates, we discussed the sensitivity and reproducibility of Ag/TiO2 nanostructure arrays for Rhodamine 6G (R6G) molecule detection. It was found that TiO2 nanosheet (TiO2(S)) array as a supporting made Ag nanoparticles have a uniform and continuous distribution, which achieved much higher SERS signals. The obtained Ag/TiO2(S) substrate had an improved enhancement factor (EF) of 4.31×105 compared with the other Ag/TiO2 nanostructure arrays of nanorods, nanotubes, and nanotrees. Furthermore, Ag/TiO2(S) active substrate showed good reproducibility with low relative standard deviation (RSD) values. Such a remarkable SERS activity could be due to the synergistic effect of electromagnetic (EM) enhancement and charge transfer (CT) enhancement. Moreover, the TiO2(S) array with high-exposed {101} facets provided a large adhesion area and generated a strong interaction with external atoms, which would produce high-density "hot spots" of SERS.

3.
Nanoscale ; 12(38): 19931-19938, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32990713

RESUMO

Salinomycin (SAL) is one of the first discovered inhibitors of human cancer stem cells (CSCs), which acts via blocking the Wnt/ß-catenin pathway. However, SAL has not been clinically used to treat human diseases due to its poor aqueous solubility and considerable toxicity. In this study, we developed salinomycin nanocrystals (SAL NCs) to treat colorectal cancer through the inhibitory enhancement of Wnt/ß-catenin signaling. The as-prepared SAL NCs exhibited excellent size distribution, stability, and improved water solubility. In vitro cellular uptake and in vivo fluorescence imaging studies showed that SAL NCs increased cellular uptake efficiency compared with free SAL. As a result, SAL NCs exhibited significant higher cytotoxicity, 1.5-3 times better Wnt inhibitory effect, and 10 times better cancer stem cell inhibitory effect than free SAL. Furthermore, compared with free SAL, SAL NCs exhibited 2 times better anti-colon tumor effect in APCmin/+ transgenic mice through oral administration. Our results indicated that SAL NCs with enhanced cellular internalization and tumor tissue accumulation may be a promising agent for colorectal cancer management.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32986410

RESUMO

The development of adhesives with superior optical and mechanical performance, solvent resistance, and reworkability is gaining increasing attention in recent years. However, traditional materials do not possess reprocessability and healing characteristics for sustainable development. Here, a superior dynamic polythiourethane (PTU) adhesive with high reprocessability was developed by introducing covalent adaptable networks (CANs). Specifically, dynamic thiocarbamate bonds (TCB) were used to prepare PTU CANs, which showed dramatically enhanced malleability and recyclability. The Young's modulus of the material was 2.0 GPa and the tensile strength was 62.7 MPa. The reprocessing temperature of CANs was reduced to 80 °C while more than 90% of their mechanical properties were retained, even after being reprocessed several times. Moreover, the highly transparent and water-resistant PTU CANs featured an excellent bonding property and reworkability for various materials including glass, with a lap shear strength of 2.9 MPa, metal (5.1 MPa), and wood (6.3 MPa), compared with commercially available adhesives. Additionally, carbon fiber-reinforced composites constructed with PTU CANs were capable of being fully recycled and reused. Importantly, laminated glass with a toughened PTU-PU elastomer interface exhibited an outstanding impact fatigue-resistance behavior, sustaining thousands of impacts. These features demonstrate that PTU CANs show great potential as sustainable materials.

5.
iScience ; 23(8): 101412, 2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32771973

RESUMO

The difficulty of obtaining reliable individual identification of animals has limited researcher's ability to obtain quantitative data to address important ecological, behavioral, and conservation questions. Traditional marking methods placed animals at undue risk. Machine learning approaches for identifying species through analysis of animal images has been proved to be successful. But for many questions, there needs a tool to identify not only species but also individuals. Here, we introduce a system developed specifically for automated face detection and individual identification with deep learning methods using both videos and still-framed images that can be reliably used for multiple species. The system was trained and tested with a dataset containing 102,399 images of 1,040 individuals across 41 primate species whose individual identity was known and 6,562 images of 91 individuals across four carnivore species. For primates, the system correctly identified individuals 94.1% of the time and could process 31 facial images per second.

6.
Org Lett ; 22(17): 6879-6883, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32813530

RESUMO

A versatile method for the construction of C(sp2)-linked cyclophane peptide macrocycles via Pd-catalyzed picolinamide-directed intramolecular arylation of aryl and alkenyl C-H bonds of amino acid side chains with aryl iodides is developed. This method provides simple and efficient access to a variety of cyclophane-braced structures from readily accessible linear peptide precursors.

7.
Sleep Med ; 75: 21-26, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32853914

RESUMO

BACKGROUND: Sleep disorders may exacerbate many physical and mental health conditions, causing difficulty function in a healthcare setting. Workers screening for the 2019 novel coronavirus (2019-nCoV) infection have a high risk of not only occupational exposure to the virus but also sleep disorders. However, the job-related factors associated with reduced sleep quality remain unclear. METHODS: All healthcare workers temporarily scheduled to screen the 2019-nCoV patients were asked to complete a self-administered questionnaire that included questions on demographics, job-related factors, and sleep quality as assessed using the Pittsburgh Sleep Quality Index (PSQI). Sleep quality was assessed over a one-month follow-up period. RESULTS: A total of 116 doctors and 99 nurses were recruited for this study. The total scheduled work time was 14.78 ± 6.69 days during follow-up. Some job-related factors, such as number of work days, years of work experience, and subjective psychological stress, were associated with changes in the PSQI score. During the study, some workers tried out cognitive behavioral therapy (CBT) for sleep disorders using methods that were available online and easily accessible. Adopting online CBT was shown to be associated with scores of components of sleep quality, sleep latency, and sleep disturbance (ß = -0.152, P = 0.01; ß = -0.175, P = 0.008; and ß = -0.158, P = 0.011, respectively). CONCLUSIONS: Healthcare workers involved in screening for 2019-nCoV experienced reduced sleep quality, and a reasonable work schedule may help with maintaining sleep quality. In addition, interventions for healthcare workers should target self-help sleep assistance.

8.
J Cell Mol Med ; 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32776630

RESUMO

Achilles tendon healing (ATH) remains an unanswered question in the field of sports medicine because it does not produce tissue with homology to the previously uninjured tissue. Oestrogen receptor ß (ERß) is involved in the injury and repair processes of tendons. Our previous study confirmed that ERß plays a role in the early stage of ATH by affecting adipogenesis, but its role in extracellular matrix (ECM) remodelling is unknown. We established a 4-week Achilles tendon repair model to investigate the mechanism through which ERß affects ATH at the very beginning of ECM remodelling phase. In vitro studies were performed using tendon-derived stem cells (TDSCs) due to their promising role in tendon healing. Behavioural and biomechanical tests revealed that ERß-deficient mice exhibit weaker mobility and inferior biomechanical properties, and immunofluorescence staining and qRT-PCR showed that these mice exhibited an erroneous ECM composition, as mainly characterized by decreased collagen type I (Col I) deposition. The changes in gene expression profiles between ERß-knockout and WT mice at 1 week were analysed by RNA sequencing to identify factors affecting Col I deposition. The results highlighted the IRF5-CCL3 axis, and this finding was verified with CCL3-treated TDSCs. These findings revealed that ERß regulates Col I deposition during ATH via the IRF5-CCL3 axis.

9.
Org Lett ; 22(15): 6209-6213, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32706585

RESUMO

A method for the construction of cyclophane-braced peptide macrocycles via Pd-catalyzed aminoquinoline-directed intramolecular C(sp3)-H arylation with aryl iodides is developed. Unlike our previous AQ-directed exo-type intramolecular C-H arylation of long alkyl tails, this endo-type C-H cyclization reaction takes places on the ß-methyl group of N-methyl alanine at the C-termini of peptides. Unusual C-N cleavage side products of Ala were observed and attributed to intramolecular deprotonation-assisted α,ß-elimination of the palladacycle intermediate.

10.
Nat Commun ; 11(1): 3780, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709882

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

11.
Eur Arch Otorhinolaryngol ; 277(11): 3067-3077, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623510

RESUMO

PURPOSE: To investigate the efficacy and safety of bencycloquidium bromide nasal spray (BCQB) in patients with persistent allergic rhinitis (PAR). METHODS: We enrolled 720 patients from 15 hospitals across China and randomly assigned them into BCQB group or placebo group (90 µg per nostril qid) to receive a 4-week treatment. Visual analog scale (VAS) for rhinorrhea, sneezing, nasal congestion, itching and overall symptoms were recorded by patients every day. Anterior rhinoscopy scoring was completed by doctors on every visit. Adverse events were recorded in detail. RESULTS: A total of 354 and 351 patients were included in BCQB group and in placebo group. Baseline information was comparable. At the end of the trial, the decrease of VAS for rhinorrhea from baseline was 4.83 ± 2.35 and 2.46 ± 2.34 in BCQB group and placebo group, respectively (P < 0.001). The change ratio from baseline of VAS for rhinorrhea in BCQB group was 72.32%, higher than 31.03% in placebo group (P < 0.001). VAS for other symptoms and overall symptoms also improved significantly in the BCQB group, while no inter-group difference was found in anterior rhinoscopy scoring. The incidence of adverse reaction was similar between the two groups. Most reactions were mild and no severe reactions happened. CONCLUSION: 90 µg BCQB per nostril four times daily is effective and safe in the treatment of rhinorrhea as well as sneezing, nasal congestion and itching for patients with PAR. RETROSPECTIVELY REGISTERED: ChiCTR2000030924, 2020/3/17.

12.
Zhongguo Zhong Yao Za Zhi ; 45(13): 3079-3084, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32726014

RESUMO

The systematic breeding method was adopted to breed a new good cultivar of Curcuma longa, named "Chuanjianghuang 1". From 2014 to 2015, two consecutive years of multi-point test were carried out in Shuangliu, Chongzhou and Wenjiang. The biological characters, phenology, agronomic characters, yield and quality indexes of "Chuanjianghuang 1" were comprehensively evaluated. The results showed that compared with local traditional species, the rhizome yield of the new cultivar "Chuanjianghuang 1" increased by 20.61%.The average content of volatile oil was higher than 24.17% and the average content of curcumin in root tuber was higher than 26.62%. The yield of root tuber increased by 54.59%.The average content of volatile oil is higher than 36.28% and the average content of curcuminoids is higher than 25.31%. Compared with "Huangsi Yujin 1", "Chuanjianghuang 1" increased the average yield of rhizome by 123.68%,the volatile oil increased by an average of 7.69%and the curcumin content increased by an average of 58.23%. The average content of volatile oil is higher than 52.82% and the average content of curcuminoids in root tuber was higher than 38.34%. The new variety "Chuanjianghuang 1" has better yield than the local traditional species, and the internal quality of rhizome and root tuber is better. Compared with "Huangsi Yujin 1", the yield of rhizome is significantly increased, and the internal quality of rhizome and root tuber is better, especially the content of curcumin in rhizome and curcuminoids in root tuber is significantly higher than that of "Huangsi Yujin 1". "Chuanjianghuang 1" is high yield, good quality, good stability and strong adaptability, which is suitable for cultivation and promotion in Chengdu Jinma River Basin, such as Shuangliu, Chongzhou, Wenjiang.


Assuntos
Diarileptanoides , Óleos Voláteis , Cruzamento , Curcuma , Rizoma
14.
Water Res ; 184: 116209, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32721765

RESUMO

Microplastics (MPs) in aquatic systems can act as a vector for various toxic contaminants, such as metal ions. Although some studies have investigated the adsorption characteristics of metal ions on MPs, the desorption behaviors of metal ions from MPs in different environments are largely unknown. Here, the adsorption of cadmium (Cd(II)) onto five different types of MPs were compared to examine the relationship between the surface characteristics and the adsorption properties of MPs. Our results showed that polyamide had the highest Cd(II) adsorption capability with a value of 1.70 ± 0.04 mg/g, followed by polyvinyl chloride (1.04 ± 0.03 mg/g), polystyrene (0.76 ± 0.02 mg/g), acrylonitrile butadiene styrene (0.65 ± 0.02 mg/g) and polyethylene terephthalate (0.25 ± 0.01 mg/g). The specific surface area and total pore volume were closely correlated with the adsorption capacity of the MPs, and the π-π interaction, electrostatic interaction and oxygen-containing functional groups played crucial roles in the adsorption of Cd(II) onto the MPs. The sorption capabilities of Cd(II) onto the MPs first increased and then decreased with increasing solution pH from 2.0 to 9.0. In addition, the adsorption capacities were suppressed with the presence of lead ions (20-80 mg/L), while the coexistence of phenanthrene had a minor impact. Interestingly, the presence of humic acid promoted the desorption of Cd(II) from the MPs both in the synthetic earthworm gut and in the sediment system. A higher desorption rate was observed in the simulated gut environment, suggesting that metal-contaminated MPs would pose higher ecological risks to macroinvertebrates. Overall, our findings provide a better understanding of the sorption mechanism of Cd(II) onto MPs and the desorption behavior under different environmental conditions in aquatic ecosystems.


Assuntos
Microbioma Gastrointestinal , Fenantrenos , Poluentes Químicos da Água , Adsorção , Cádmio , Ecossistema , Concentração de Íons de Hidrogênio , Chumbo , Microplásticos , Plásticos , Água , Poluentes Químicos da Água/análise
15.
Zool Res ; 41(4): 458-464, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32521577

RESUMO

The egg laying behavior of brood parasites is at the heart of studies on host co-evolution. Therefore, research on egg laying behavior can improve our understanding of brood parasitism and associated processes. Over a seven year study period, we monitored 455 oriental reed warbler ( Acrocephalus orientalis) nests during the egg laying period, 250 of which were parasitized by common cuckoos ( Cuculus canorus). We collected 53 clear videos of common cuckoo parasitism, analyzed all recorded parasitic behavior in detail, and summarized the process of brood parasitism. Furthermore, based on analyses of the field video recordings, we propose a new explanation for egg removal behavior, namely the delivery hypothesis, i.e., egg pecking and biting by cuckoos may facilitate fast egg-laying and parasitism by reducing host attention and attack, with egg removal a side effect of egg pecking and biting. We concluded that common cuckoos change their behavior when hosts are present at the nest, with a set of behaviors performed to deal with host attack and successfully complete parasitic egg-laying regardless of time of day.

16.
Med Sci Monit ; 26: e923328, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32369458

RESUMO

BACKGROUND Inflammation after tendon-bone junction injury results in the formation of excessive scar tissue and poor biomechanical properties. Recent research has shown that exosomes derived from bone marrow stromal cells (BMSCs) can modulate inflammation during tissue healing. Thus, our study aimed to enhance tendon-bone healing by use of BMSC-derived exosomes (BMSC-Exos). MATERIAL AND METHODS The mouse tendon-bone reconstruction model was established, and the mice were randomly divided into 3 groups: the control group, the hydrogel group, and the hydrogel+exosome group, with 30 mice in each group. At 7 days, 14 days, and 1 month after surgery, tendon-bone junction samples were harvested, and the macrophage polarization and tendon-bone healing were evaluated based on histology, immunofluorescence, and quantitative RT-PCR (qRT-PCR) analysis. RESULTS In the early phase, we observed significantly higher numbers of M2 macrophages and more anti-inflammatory and chondrogenic-related factors in the hydrogel+BMSC-Exos group compared with the control group and the hydrogel group. The M1 macrophages and related proinflammatory factors decreased. Cell apoptosis decreased in the hydrogel+BMSC-Exos group, while cell proliferation increased; in particular, the CD146+ stem cells substantially increased. At 1 month after surgery, there was more fibrocartilage in the hydrogel+BMSC-Exos group than in the other groups. Biomechanical testing showed that the maximum force, strength, and elastic modulus were significantly improved in the hydrogel+BMSC-Exos group. CONCLUSIONS Our study provides evidence that the local administration of BMSC-Exos promotes the formation of fibrocartilage by increasing M2 macrophage polarization in tendon-to-bone healing, leading to improved biomechanical properties. These findings provide a basis for the potential clinical use of BMSC-Exos in tendon-bone repair.

17.
ACS Appl Mater Interfaces ; 12(23): 26432-26443, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32429664

RESUMO

The development of a highly effective photosensitizer (PS) that can be activated with a low-power single light is a pressing issue. Herein, we report a PS for synergistic photodynamic and photothermal therapy constructed through self-assembly of poly(selenoviologen) on the surface of core-shell NaYF4:Yb/Tm@NaYF4 upconversion nanoparticles. The hybrid UCNPs/PSeV PS showed strong ROS generation ability and high photothermal conversion efficiency (∼52.5%) under the mildest reported-to-date irradiation conditions (λ = 980 nm, 150 mW/cm2, 4 min), leading to a high efficiency in killing methicillin-resistant Staphylococcus aureus (MRSA) both in vitro and in vivo. Remarkably, after intravenous injection, the reported PS accumulated preferentially in deep MRSA-infected tissues and achieved an excellent therapeutic index. This PS design realizes a low-power single-NIR light-triggered synergistic phototherapy and provides a simple and versatile strategy to develop safe clinically translatable agents for efficient treatment of deep tissue bacterial inflammations.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32424859

RESUMO

The chemical structures and topologies of the crosslinks in supramolecular networks play a crucial role in their properties and functions. Herein, the preparation of a type of poly(N-isopropylacrylamide) (PNIPAAM)-based supramolecular networks crosslinked by emissive hexagonal metallacycles is presented. The topological connections in these networks greatly affect their properties, as evidenced by their differences in absorption, emission, lower critical solution temperature, and modulus along with the variation of crosslinking densities. The integration of PNIPAAM and metallacycles in the networks benefits them improved bioavailability, making them serve as reagents for bacterial imaging and killing. This study provides a strategy to prepare cavity-crosslinked polymer networks for antibacterial applications.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32383855

RESUMO

In the present study, a comparative study on the influence of different laminated stacks driven by aomic layer deposition (ALD) on the interfacial and electrcial properties of high-k/Ge gate stacks passivated by trimethylaluminum (TMA) has been performed in detail via X-ray photoelectron spectroscopy (XPS) and electrical measurements. XPS measurements indicate that HfO2/Al2O3/Ge gate stacks can effectively inhibit the formation of Ge suboxides and a low-k germanate layer. Compared to Al2O3/HfO2 and HfO2/Al2O3/HfO2 gate stacks, the HfO2/Al2O3/Ge metal oxide semiconductor (MOS) capacitors exhibited improved electrical performance, including a maximum permittivity of 18.15, disappearing hysteresis, an almost neglected flat band voltage of 0.01 V, and a minimum leakage current density of 3.82 × 10-8 A/cm2 at room temperature. Especially, the leakage current mechanisms of Ge-MOS capacitors based on different laminated stacks measured at room temperature and low temperature (77-327 K) have been comprehensively analyzed. By comparing three different laminated gate stacks, it can be inferred that HfO2/Al2O3/Ge gate stacks have a potential application prospect in Ge-based microelectronic devices.

20.
Am J Primatol ; 82(7): e23142, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452078

RESUMO

Depicting a taxonomic group's evolutionary trajectory as a function of changes in the geographical landscape and its historical distribution is critical for constructing informed conservation strategies. Based on fossil sites from the Pliocene to the Holocene, and historical records since 1175 AD, we established macaques' dispersal pathways into and through China. These routes include internal pathways starting from the southeast corner of the Qinghai-Tibet Plateau and Mts. Hengduan in western China, and the routes through the estuaries of the three major rivers (Yangtze, Yellow, and Pearl). Our results indicate that macaques used the three rivers and avoided the higher elevation of the plateaus to promote their radiation. They occupied the whole mainland and islands in the Pleistocene and experienced shrunken distribution in the Holocene due to climate changes and human-induced activities. A prominent China-wide reduction occurred between 1817 and 1917; and a remarkable retraction from central China happened between 1918 and 2018 following further eco-social development and human expansion in central China, particularly since the second half of the last century. Starting in 1175 there was a restriction of range to higher altitudes, so that macaques have contracted their range to the west, and the Qinghai-Tibet Plateau and Mts. Hengduan have become an important sanctuary. We predict that if the current climate and human-induced changes are not reversed by decisive conservation actions, macaques in east and central China will likely be extinct in the near future.

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