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1.
Artigo em Inglês | MEDLINE | ID: mdl-33625225

RESUMO

Enhancing the monodispersity and surface properties of nanoporous zeolitic imidazolate frameworks (ZIFs) are crucial for maximizing their performance in advanced nanocomposites for separations. Herein, we developed an in situ method to synthesize monodispersed ZIF-8 nanocrystals with unique dopamine (DA) surface decoration layer (ZIF-8-DA) in an aqueous solution at room temperature. Interestingly, the in situ formation of the monodispersed ZIF-8-DA nanocrystals experiences a triple-stage crystallization process, resulting in a rhombic dodecahedron architecture, which is greatly different from the synthesis of conventional ZIF-8. The crystallinity and abundant microporosity of ZIF-8-DA nanocrystals is well maintained even with the DA surface decoration. Owing to the advanced surface compatibility and pore properties of ZIF-8-DA, ZIF-8-DA/Matrimid mixed-matrix membranes exhibit both higher gas permeability and selectivity than the pristine Matrimid polyimide membrane, which breaks out the traditional "trade-off" phenomena between permeability and selectivity.

2.
Adv Mater ; : e2008722, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33634900

RESUMO

Persistent-luminescence phosphors (PLPs) have a wide variety of applications in the fields of photonics and biophotonics due to their ultralong afterglow lifetime. However, the existing PLPs are charged and recharged with short-wavelength high-energy photons or inconvenient and potentially risky X-ray beams. To date, deep tissue penetrable NIR light has mainly been used for photostimulated afterglow emission, which continues to decay and weaken after each cycle, Herein, a new paradigm of trap energy upconversion-like near-infrared (NIR) to near-infrared light rejuvenateable persistent luminescence in bismuth-doped calcium stannate phosphors and nanoparticles is reported. In contrast to the existing PLPs and persistent-luminescence nanoparticles, the materials enable the occurrence of a reversed transition of the carriers from a deep-level energy trap to a shallow-level trap upon excitation by low-energy NIR photons. Thus these new materials can be charged circularly via deep-tissue penetrable NIR photons, which is unable to be done for existing PLPs, and emit afterglow signals. This conceptual work will lay the foundation to design new categories of NIR-absorptive-NIR-emissive PLPs and nanoparticles featuring physically harmless and deep tissue penetrable NIR light renewability and sets the stage for numerous biological applications, which have been limited by current materials.

3.
Anal Chim Acta ; 1147: 99-107, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33485588

RESUMO

Single-walled carbon nanotube-based field effect transistors (SWCNT-FETs) are ideal candidates for fabricating sensors and have been widely used for chemical sensing applications. SWCNT-FETs have low selectivity because of the environmentally sensitive electronic properties of SWCNTs, and SWCNT-FETs also show a high noise signal and poor sensitivity because of charge trapping from Si-OH hydration of the SiO2/Si substrate on the SWCNTs. Herein, poly (4-vinylpyridine) (P4VP) was used for noncovalent attachment to SWCNTs and selective binding to copper ions (Cu2+). Importantly, the introduction of a hafnium-oxide (HfO2) layer through atomic layer deposition (ALD) overcame the charge trapping by SiO2 hydration and remarkably decreased the interference signal. The sensitivity of the P4VP/SWCNT/HfO2-FET sensor for Cu2+ was 7.9 µA µM-1, which was approximately 100 times higher than that of the P4VP/SWCNT/SiO2-FET sensor, and its limit of detection (LOD) was as low as 33 pmol L-1. Thus, the P4VP/SWCNT/HfO2-FET sensor is a promising candidate for the development of Cu2+-selective sensors and can be designed for the large-scale manufacturing of custom-made sensors in the future.

4.
Materials (Basel) ; 14(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33450936

RESUMO

Reversible phase-change behaviors of Ge-Sb-Te based superlattices (GST-SL) were studied by ab initio molecular dynamics (AIMD) simulations based on three models containing Ge/Sb intermixing, namely the Petrov-mix, Ferro-mix, and Kooi-mix models. The flipping behavior of Sb atoms was found in all the three GST-SL models in the melting process. Among them the Kooi-mix model exhibited the best stability, and the analyses of bond length distribution and electron localization function provided a better explanation on the phase transition of GST-SL. Finally, we proposed a fast switching model for GST-SL based on Sb flipping.

5.
Nat Commun ; 12(1): 122, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402702

RESUMO

Photolysis has enabled the occurrence of numerous discoveries in chemistry, drug discovery and biology. However, there is a dearth of efficient long wavelength light mediated photolysis. Here, we report general and efficient long wavelength single photon method for a wide array of photolytic molecules via triplet-triplet annihilation photolysis. This method is versatile and "LEGO"-like. The light partners (the photosensitizers and the photolytic molecules) can be energetically matched to adapt to an extensive range of electromagnetic spectrum wavelengths and the diversified chemical structures of photoremovable protecting groups, photolabile linkages, as well as a broad array of targeted molecules. Compared to the existing photolysis methods, our strategy of triplet-triplet annihilation photolysis not only exhibits superior reaction yields, but also resolves the photodamage problem, regardless of whether they are single photon or multiple photon associated. Furthermore, the biological promise of this "LEGO" system was illustrated via developing ambient air-stable nanoparticles capable of triplet-triplet annihilation photolysis.

6.
Small ; 17(6): e2005728, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33470521

RESUMO

In order to achieve better antitumor therapeutic efficacy and inhibit tumor metastasis, a multifunctional nanovaccine based on L-arginine (LA)-loaded black mesoporous titania (BMT) is fabricated. In this system, LA is utilized as the exogenous NO supplementation for gas therapy, and BMT is served as acoustic sensitizer for sonodynamic therapy. The ultrasound (US) as the exogenous stimulus can simultaneously trigger BMT and LA to produce singlet oxygen (1 O2 ) and NO gas at tumor sites, respectively. Interestingly, 1 O2 from US-excited BMT can promote the oxidation of LA to produce more NO. The high concentration of 1 O2 and NO in cancer cell can cause intracellular strong oxidative stress level and DNA double-strand breaks to induce cancer cell apoptosis ultimately. The US-triggered BMT@LA "nanovaccine" combining with immune checkpoint inhibitor PD-L1 antibody (αPD-L1) can induce strong antitumor immune response thus effectively killing primary tumors and further inhibiting metastatic tumors. Hence, BMT@LA-based "nanovaccine" combining with αPD-L1 checkpoint blockade treatment can realize synergetic sonodynamic/gas/immunotherapy with enhanced antitumor therapeutic effects.

7.
EMBO Mol Med ; 13(2): e12993, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33337582

RESUMO

Antisense oligonucleotide (AO)-mediated exon-skipping therapies show promise in Duchenne muscular dystrophy (DMD), a devastating muscular disease caused by frame-disrupting mutations in the DMD gene. However, insufficient systemic delivery remains a hurdle to clinical deployment. Here, we demonstrate that MOTS-c, a mitochondria-derived bioactive peptide, with an intrinsic muscle-targeting property, augmented glycolytic flux and energy production capacity of dystrophic muscles in vitro and in vivo, resulting in enhanced phosphorodiamidate morpholino oligomer (PMO) uptake and activity in mdx mice. Long-term repeated administration of MOTS-c (500 µg) and PMO at the dose of 12.5 mg/kg/week for 3 weeks followed by 12.5 mg/kg/month for 3 months (PMO-M) induced therapeutic levels of dystrophin expression in peripheral muscles, with up to 25-fold increase in diaphragm of mdx mice over PMO alone. PMO-M improved muscle function and pathologies in mdx mice without detectable toxicity. Our results demonstrate that MOTS-c enables enhanced PMO uptake and activity in dystrophic muscles by providing energy and may have therapeutic implications for exon-skipping therapeutics in DMD and other energy-deficient disorders.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33278319

RESUMO

Gas-separation polymer membranes display a characteristic permeability-selectivity trade-off that has limited their industrial use. The most comprehensive approach to improving performance is to devise strategies that simultaneously increase fractional free volume, narrow free volume distribution, and enhance sorption selectivity, but generalizable methods for such approaches are exceedingly rare. Here, we present an in situ crosslinking and solid-state deprotection method to access previously inaccessible sorption and diffusion characteristics in amine-functionalized polymers of intrinsic microporosity. Free volume element (FVE) sizes can be increased while preserving a narrow FVE distribution, enabling below-upper bound polymers to surpass the H 2 /N 2 , H 2 /CH 4 , and O 2 /N 2 upper bounds and improving CO 2 -based selectivities by 200%. This approach can transform polymers into chemical analogues with improved performance, thereby overcoming traditional permeability-selectivity trade-offs.

9.
Hisp Health Care Int ; : 1540415320976643, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33287567

RESUMO

INTRODUCTION: Explanations for racial disparities in preterm birth (PTB) are elusive, especially when comparing high rates in some racial groups with low rates in Mexican-immigrant women. The purpose of this study was to examine potential protective factors against PTB such as religiosity and acculturation. METHODS: This study was a prospective investigation of Mexican- and U.S.-born pregnant women. Women were recruited from a low-income-serving prenatal clinic in Texas. Survey instruments included socioeconomic variables, acculturation, and religiosity/spirituality (R/S). Logistic regression was used to examine the associations between acculturation, religiosity, and PTB. Because of the low prevalence of PTB in our sample, we were not able to adjust for confounding characteristics. RESULTS: Ninety-one low-income women, mostly Mexican immigrants, participated in the study. PTB in our sample was lower than the national average in the United States (5.5% vs. 9.9%) and was positively but moderately associated with high R/S. R/S scores were high, particularly for frequency of attendance, prayer, and religious coping. Women with lower acculturation had higher scores on the religiosity measures. CONCLUSION: Further research is needed with a larger sample to include other ethnic and racial minorities to more fully understand the relationships between acculturation, religiosity, and PTB.

11.
Mol Ther ; 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333294

RESUMO

Duchenne muscular dystrophy (DMD) is a devastating genetic disorder that leads to compromised cellular membranes, caused by the absence of membrane-bound dystrophin protein. Muscle membrane leakage results in disrupted intracellular homeostasis, protein degradation, and muscle wasting. Improving muscle membrane integrity may delay disease progression and extend the lifespan of DMD patients. Here, we demonstrate that exosomes, membranous extracellular vesicles, can elicit functional improvements in dystrophic mice by improving muscle membrane integrity. Systemic administration of exosomes from different sources induced phenotypic rescue and mitigated pathological progression in dystrophic mice without detectable toxicity. Improved membrane integrity conferred by exosomes inhibited intracellular calcium influx and calcium-dependent activation of calpain proteases, preventing the degradation of the destabilized dystrophin-associated protein complex. We show that exosomes, particularly myotube-derived exosomes, induced functional improvements and alleviated muscle deterioration by stabilizing damaged muscle membrane in dystrophic mice. Our findings suggest that exosomes may have therapeutic implications for DMD and other diseases with compromised membranes.

12.
Clin Infect Dis ; 71(Supplement_4): S337-S362, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33367581

RESUMO

The Chinese guidelines for IAI presented here were developed by a panel that included experts from the fields of surgery, critical care, microbiology, infection control, pharmacology, and evidence-based medicine. All questions were structured in population, intervention, comparison, and outcomes format, and evidence profiles were generated. Recommendations were generated following the principles of the Grading of Recommendations Assessment, Development, and Evaluation system or Best Practice Statement (BPS), when applicable. The final guidelines include 45 graded recommendations and 17 BPSs, including the classification of disease severity, diagnosis, source control, antimicrobial therapy, microbiologic evaluation, nutritional therapy, other supportive therapies, diagnosis and management of specific IAIs, and recognition and management of source control failure. Recommendations on fluid resuscitation and organ support therapy could not be formulated and thus were not included. Accordingly, additional high-quality clinical studies should be performed in the future to address the clinicians' concerns.

13.
Gland Surg ; 9(5): 1346-1353, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33224809

RESUMO

Background: The exact factors and mechanisms involved in the development of hematoma after breast ultrasound (US)-guided vacuum-assisted biopsy (VAB) are not clear. This study aimed to analyze the occurrence, prognosis, and risk factors of hematoma after US-guided VAB for the removal of benign breast lesions. Methods: This was a retrospective study of consecutive female patients with breast lesions (BI-RADS 3/4a/4b and confirmed as benign by core needle biopsy) removed by percutaneous excisional biopsy by US-guided VAB at the Beijing Chaoyang Hospital from April 2016 to December 2018. Univariable analyses were conducted to identify the factors associated with hematoma (age, nodule size, laterality, nodule location, number of nodules, BI-RADS classification of ultrasound, pathology, breast shape, menstrual period, efficacy time of bandage, and hemostatic agents). Multivariable analysis was performed to identify the factors independently associated with hematoma. Results: A total of 293 patients (343 breast lesions) were included. Lesion removal was successful in all cases. Hematomas ≥1 cm were found in 39 patients. Finally, 38 (97.4%) hematomas were absorbed completely within 6 months. The multivariable logistic regression analysis revealed that lesion size (P<0.001; OR: 5.775; 95% CI: 2.752-12.121), number of lesions (P=0.011; OR: 3.205, 95% CI: 1.311-7.834), and the efficacy time of bandage 12-24 h (P=0.003; OR: 5.257, 95% CI: 1.792-15.421) were independently associated with hematoma occurrence after US-guided VAB excision of breast lesions. A lesion size cut-off of 23.4 mm (AUC 0.764, 95% CI: 0.692-0.837; 59.0% sensitivity; 80.3% specificity; 77.5% accuracy; P<0.001) could predict hematoma occurrence. Conclusions: US-guided excisional VAB can effectively remove benign breast lesions. The factors independently associated with postoperative hematoma are lesion size, lesion number, and effective postoperative compression time of bandage.

14.
Mol Ther Nucleic Acids ; 22: 196-197, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33230426

RESUMO

[This corrects the article DOI: 10.1016/j.omtn.2018.06.005.].

15.
Adv Mater ; : e2003881, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33145880

RESUMO

Afterglow nanoparticles (AGNPs) possessing inherently long lifetime with tailorable emission colors and uniform size have long been sought due to their time-gating-free high-contrast multiplexing imaging. Herein, via a straightforward template method, it is reported that such multicolor AGNPs can be accomplished. The resultant AGNPs exhibit a series of tunable afterglow emissions, including blue, yellow, green, and white. These multicolor AGNPs are found to be highly bright, enabling them to perform high-contrast multichannel afterglow imaging in vitro and in vivo without the use of any complicated time-gating algorithms or systems, which existing tools are unable to do.

16.
J Am Chem Soc ; 142(43): 18460-18470, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33074671

RESUMO

Organic triplet-triplet annihilation upconversion (TTA-UC) materials have considerable promise in areas as broad as biology, solar energy harvesting, and photocatalysis. However, the development of highly efficient near-infrared (NIR) light activatable TTA-UC systems remains extremely challenging. In this work, we report on a method of systematically tailoring an annihilator to attain such outstanding systems. By chemical modifications of a commonly used perylene annihilator, we constructed a family of perylene derivatives that have simultaneously tailored triplet excited state energy (T1) and singlet excited state energy (S1), two key annihilator factors to determine TTA-UC performance. Via this method, we were able to tune the TTA-UC system from an endothermic type to an exothermic one, thus significantly elevating the upconversion performance of NIR light activatable TTA upconversion systems. In conjunction with the photosensitizer PdTNP (10 µM), the upconversion efficiency using the optimal annihilator (100 µM) identified in this study was measured to be 14.1% under the low-power density of NIR light (100 mW/cm2, 720 nm). Furthermore, using such a low concentration of perylene derivative, we demonstrated that the optimal TTA-UC pair developed in our study can act as a highly effective light wavelength up-shifter to enable NIR light to drive a photoredox catalysis that otherwise requires visible light. We found that such an NIR driven method is highly effective and can even surpass directly visible light driven photoredox catalysis. This method is important for photoredox catalysis as NIR light can penetrate much deeper in colored photoredox catalysis reaction solutions, especially when done in a large-scale manner. Furthermore, this TTA-UC mediated photoredox catalysis reaction is found to be outdoor sunlight operable. Thus, our study provides a solution to enhance NIR activatable organic upconversion and set the stage for a wide array of applications that have previously been limited by the suboptimal efficiency of the existing TTA upconversion materials.

17.
Adv Healthc Mater ; : e2000321, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-33034955

RESUMO

Light-controlled sequential photolysis from a single nanoparticle is a challenge for controlled release. A wavelength-selective sequential photolysis from single gold nanoparticles is reported for the first time. In particular, it is also demonstrated that such nanoparticle can be used to sequentially release two payloads in living cells. In principle, this system can be extended to sequential release of multiple different types of payloads by rational design of diverse photocleavable linkers. It is expected that this work can provide a new tool for better orderly controlling cellular events that request high spatiotemporal manners.

18.
Sci Adv ; 6(41)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028518

RESUMO

Almost all covalent organic framework (COF) materials conventionally fabricated by solvothermal method at high temperatures and pressures are insoluble and unprocessable powders, which severely hinder their widespread applications. This work develops an effective and facile strategy to construct flexible and free-standing pure COF membranes via the liquid-liquid interface-confined reaction at room temperature and atmospheric pressure. The aperture size and channel chemistry of COF membranes can be rationally designed by bridging various molecular building blocks via strong covalent bonds. Benefiting from the highly-ordered honeycomb lattice, high solvent permeances are successfully obtained and follow the trend of acetonitrile > acetone > methanol > ethanol > isopropanol. Interestingly, the imine-linked COF membrane shows higher nonpolar solvent permeances than b-ketoenamine-linked COF due to their difference in pore polarity. Both kinds of COF membranes exhibit high solvent permeances, precise molecular sieving, excellent shape selectivity, and sufficient flexibility for membrane-based separation science and technology.

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