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1.
J Am Chem Soc ; 146(21): 14685-14696, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38717074

RESUMEN

The exploration of new polymer materials required the development of efficient, economic, robust, and scalable synthetic routes, taking energy consumption, environmental benefit, and sustainability into overall consideration. Herein, through retro-polymerization analysis of functional aromatic polythioureas, a multicomponent reaction of elemental sulfur, CH2Cl2, and aromatic amines was designed with the assistance of fluoride, and efficient, economic, and robust multicomponent polymerizations (MCPs) of these three abundantly available cheap monomers, elemental sulfur, CH2Cl2, and aromatic diamines, were developed to realize scalable conversion directly from sulfur to a series of functional aromatic polythioureas with high molecular weights (Mn up to 50,800 g/mol) in excellent yields (up to 98%). The synergistic cooperation of the strong and selective coordination of thiourea with gold ions and the redox property of aromatic polythiourea enable in situ reduction of Au3+ to elemental gold under a normal bench condition. Furthermore, the functional aromatic polythiourea could be chemically recycled through aminolysis with NH3·H2O to afford a diamine monomer in 83% isolated yield. The development of elemental sulfur-based MCP has brought the opportunity to access cost-effective and sustainable sulfur-containing functional polymer materials, which is anticipated to provide a solution for the utilization of sulfur waste and making profitable polymer materials.

2.
Clin Nephrol ; 101(6): 287-297, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38511675

RESUMEN

OBJECTIVE: Membranous nephropathy is a leading cause of adult-onset nephrotic syndrome. Peripheral T cells and myeloid-derived suppressor cells (MDSCs) are closely associated with autoimmune diseases, while their exact roles and interaction in these processes are unclear. Here, we studied the roles of T cells, MDSCs, and their subsets in patients with idiopathic membranous nephropathy (IMN). MATERIALS AND METHODS: 35 IMN patients and 30 healthy controls were included in this retrospective study. Flow cytometry was performed to determine the phenotype of human T cells and MDSCs in peripheral blood mononuclear cells (PBMCs). Anti-PLA2R was measured by ELISA. Values ≥ 20 RU/mL were defined as positive and < 14 RU/mL as negative. RESULTS: A higher ratio of CD4/CD8 T cells with a lower proportion of Tregs, a remarkably lower proportion of G-MDSCs (but not M-MDSCs), lower frequency of PD-L2+G-MDSCs, and higher frequency of PD-L1+M-MDSCs were found in IMN patients compared to healthy controls. The ratio of CD4/CD8 T cells was higher, and the frequencies of PD-1+CD4+ T cells, CTLA-4+CD4+ T cells, PD-1+Tregs, and CTLA-4+Tregs were lower in PBMCs of PLA2R-positive IMN patients compared to PLA2R-negative IMN patients. CONCLUSION: Tregs and G-MDSCs were reduced in the circulation of the IMN patients, which may promote understanding of the crucial functions that are mediated by these cells in the pathogenesis of IMN.


Asunto(s)
Glomerulonefritis Membranosa , Células Supresoras de Origen Mieloide , Humanos , Glomerulonefritis Membranosa/inmunología , Glomerulonefritis Membranosa/sangre , Masculino , Femenino , Células Supresoras de Origen Mieloide/inmunología , Persona de Mediana Edad , Estudios Retrospectivos , Adulto , Receptores de Fosfolipasa A2/inmunología , Citometría de Flujo , Linfocitos T CD8-positivos/inmunología , Linfocitos T Reguladores/inmunología , Estudios de Casos y Controles , Relación CD4-CD8 , Anciano , Receptor de Muerte Celular Programada 1/sangre , Receptor de Muerte Celular Programada 1/metabolismo
3.
J Am Chem Soc ; 145(51): 28204-28215, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38099712

RESUMEN

With the increasing demand for functional polythiophenes in extensive applications such as organic solar cells, electronic skins, thermoelectric materials, and field effect transistors, efficient and economic synthetic approaches for polythiophenes are urgently required. In this work, KOH-assisted polymerizations of elemental sulfur and alkynones were developed to directly afford polythiophenes with various backbones, regioselective structures, and high molecular weights (Mns up to 20700 g/mol) in high yields (up to 97%) at 80 °C in 30 min. When the same polymerization was conducted at room temperature, stable and unique poly(1,4-dithiin)s (Mns up to 21800 g/mol) could be rapidly obtained in high yields (up to 87%) in 10 min. The temperature-controlled KOH-assisted polymerizations of sulfur and alkynones possessed high efficiency, mild conditions, and simple operation, which had provided an economic, efficient, and convenient approach for the direct conversion from elemental sulfur to functional polythiophenes and poly(1,4-dithiin)s with the in situ constructed aromatic or nonaromatic heterocycles embedded in the polymer backbones, demonstrating great synthetic simplicity, high efficiency, good selectivity, and robustness. It is anticipated to accelerate the development of semiconducting polymer materials and their applications.

4.
Am J Nephrol ; 54(11-12): 451-470, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37793354

RESUMEN

INTRODUCTION: Dysbiosis of the intestinal microbiome and related metabolites have been observed in chronic kidney disease, yet their roles in idiopathic membranous nephropathy (IMN) are poorly understood. METHODS: In this study, we describe the variation of intestinal bacteria and fecal metabolites in patients with IMN in Chinese population. Stool samples were collected from 41 IMN patients at the beginning of diagnosis confirmation and 41 gender- and age-matched healthy control (HC). Microbial communities are investigated by sequencing of 16S rRNA genes and functional profiles predicted using Tax4Fun, and the correlation between intestinal bacteria and IMN clinical characteristics is also analyzed. Untargeted metabolomic analysis is performed to explore the relationship between colon's microbiota and fecal metabolites. RESULTS: IMN gastrointestinal microbiota demonstrates lower richness and diversity compared to HC, and exhibits a marked taxonomic and inferred functional dysbiosis when compared to HC. Some genera are closely related to the clinical parameters, such as Citrobacter and Akkermansia. Twenty characteristic microbial biomarkers are selected to establish a disease prediction model with a diagnostic accuracy of 93.53%. Fecal metabolomics shows that tryptophan metabolism is reduced in IMN patients but uremic toxin accumulation in feces is not noticeable. Fecal microbiota transplantation demonstrates that gut dysbiosis impairs gut permeability in microbiota-depleted mice and induces NOD-like receptor activation in the kidneys. CONCLUSIONS: Clarifying the changes in intestinal microbiota in IMN patients will help further know the pathogenesis of this disease, and microbiota-targeted biomarkers will provide a potentially powerful tool for diagnosing and treating IMN.


Asunto(s)
Microbioma Gastrointestinal , Glomerulonefritis Membranosa , Humanos , Ratones , Animales , Microbioma Gastrointestinal/fisiología , Disbiosis , ARN Ribosómico 16S/genética , Biomarcadores
5.
Phys Chem Chem Phys ; 26(1): 373-380, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38073608

RESUMEN

Metal halide perovskites are particularly emerging for optoelectronic applications in light-emitting diodes, photodetectors, and solar cells due to their flourishing photophysical properties. However, the poor stability of three-dimensional (3D) lead halide perovskite nanocrystals (NCs) significantly hampers their optoelectronics and photovoltaics applications. Embedding 3D perovskites into zero-dimensional (0D) perovskite crystals and doping ions of appropriate elements into host lattices provide effective approaches to improve the stability and optical-electronic performance. In this study, millimeter-scale Mn-doped and undoped CsPbBr3/Cs4PbBr6 perovskite crystals were successfully fabricated by a one-step slow cooling method. We systematically investigated the effects of Mn2+ ion doping on the PL performance and stability of CsPbBr3/Cs4PbBr6 crystals. Compared with undoped crystals, the existence of Mn2+ ions not only blue-shifted the PL peak but also improved the luminescence performance and stability of the prepared millimeter-sized crystals. Moreover, doping Mn2+ ions can increase the proportion of radiative recombination at low temperature, which may be because Mn2+ ions can effectively accelerate the decay of a dark exciton by the magnetic mixing of bright and dark excitons. In addition, green LED devices with high efficiency packaged as-grown crystals are explored, which promises further application in display backlights.

6.
J Craniofac Surg ; 34(8): 2563-2568, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37782137

RESUMEN

Scaffolds play an important role in bone tissue engineering. The ideal engineered scaffold needs to be biocompatible, bioactive, and able to regulate immune cells to enhance bone regeneration. In this study, magnesium (Mg)-contained poly(lactic-co-glycolic acid) (PLGA) scaffolds (hereinafter, referred to as PLGA-2Mg) were fabricated by 3-dimensional printing using a mixture of PLGA and MgSO 4 powder. Poly(lactic-co-glycolic acid) scaffolds (hereinafter, referred to as PLGA) were also fabricated by 3-dimensional printing and were used as control. The biocompatibility, immunoregulatory ability, and osteogenic properties of PLGA-2Mg were analyzed and compared with those of PLGA. The results indicate that the incorporation of Mg increased the Young modulus and surface roughness of the scaffold, but did not affect its degradation. The PLGA-2Mg further promoted the adhesion and proliferation of MC3T3-E1 cells compared with PLGA, which indicates its improved biocompatibility and bioactivity. In addition, PLGA-2Mg inhibited the polarization of RAW 264.7 cells toward the M1 phenotype by down-regulating the IL-1ß , IL-6 , and iNOs gene expression when challenged with lipopolysaccharide stimulation. In contrast, it promoted the polarization of RAW 264.7 cells toward the M2 phenotype by up-regulating the TGF-ß , IL-10 , and Arg-1 gene expression without lipopolysaccharide stimulation. Finally, MC3T3-E1 cells were cocultured with RAW 264.7 cells and scaffolds using a transwell system. It was found that the expression level of osteogenic-related genes ( ALP , COL-1 , BMP2 , and BSP ) was significantly upregulated in the PLGA-2Mg group compared with that in the PLGA group. Consequently, PLGA-2Mg with increased biocompatibility and bioactivity can promote osteogenesis through immunoregulation and has the potential to be used as a novel scaffold in bone tissue engineering.


Asunto(s)
Magnesio , Osteogénesis , Humanos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Magnesio/farmacología , Andamios del Tejido , Ácido Poliglicólico , Glicoles , Lipopolisacáridos , Ingeniería de Tejidos/métodos
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(6): 961-965, 2023 Dec 30.
Artículo en Zh | MEDLINE | ID: mdl-38173108

RESUMEN

Since end-stage renal disease leads to a variety of problems such as disability,reduced quality of life,and mental and psychological disorders,it has become a serious public health problem around the globe.Renal palliative care integrates palliative care philosophy in the care for patients with end-stage renal disease.As a planned,comprehensive,patient-centered care,renal palliative care focuses on the patient's symptoms and needs,aiming to reduce the suffering throughout the course of the disease,including but not limited to end-of-life care.This study reports the palliative care practice for a patient on maintenance dialysis in the Blood Purification Center of Peking Union Medical College Hospital and reviews the present situation of palliative care in end-stage renal disease.


Asunto(s)
Fallo Renal Crónico , Cuidado Terminal , Humanos , Cuidados Paliativos/psicología , Calidad de Vida , Fallo Renal Crónico/terapia , Cuidado Terminal/psicología , Diálisis Renal/psicología
8.
Phys Chem Chem Phys ; 24(41): 25434-25439, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36250550

RESUMEN

Perovskite microcrystals have attracted wide attention and have been applied in extensive optical applications. The CsPbX3 perovskite poses a great threat to the environment due to the presence of lead (Pb), and there is an urgent need to improve the photoluminescence quantum yield. Therefore, a lead-free perovskite microcrystal material Cs2RbxAg1-xIn0.875Bi0.125Cl6 with a high photoluminescence quantum yield (PLQY) was synthesized by a convenient hydrothermal method, with comprehensive characterization of both the structure and optical performance at varying Rb ratios. Optimal properties were observed at x = 0.15 with bright white emission and a PLQY of 32.15%. Superior stability of the novel material in ethanol was observed under the radiation of an excitation light of 365 nm. Interestingly, a blue shift of the emission peak occurred after exposure to humid air, possibly due to the reconstruction of the crystal structure. Moreover, a LED device packaged with this novel material was developed with a desirable color temperature of 3190 K, promising for further lighting applications.

9.
Phys Chem Chem Phys ; 24(29): 17471-17478, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35822339

RESUMEN

The Cl-initiated oxidation of methacrolein (MACR, C4H6O) under NOx-free conditions has been investigated in a fast flow tube by using a home-made vacuum ultraviolet (VUV) photoionization mass spectrometer complemented by high-level theoretical calculations. The key species such as intermediates and radicals together with products involved in the oxidation are observed online and confirmed in photoionization mass spectra. The reaction potential energy surfaces of the transient C4H5O and C4H6OCl radicals, formed from the hydrogen-abstraction reaction and the addition reaction of MACR with Cl atoms, with oxygen have been theoretically calculated to illuminate the formation of the peroxy radicals of C4H5OO2 and C4H6OClO2. The photoionization processes of these peroxy radicals, whose cations are not stable, and their individual self-reactions as well as bimolecular reactions with HO2 radical are studied and discussed. In addition, kinetic experiments are also performed to get the time evolution of specific products and compared with theoretical models, providing a detailed insight into the reaction mechanism of the Cl-initiated oxidation of MACR.

10.
BMC Nephrol ; 23(1): 155, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459111

RESUMEN

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) may coexist with rheumatoid arthritis (RA). However, it is unclear whether the manifestations of AAV with and without coexisting RA are similar. This observational study aimed to investigate the clinicopathological manifestations of AAV with coexisting RA and to explore potential predictors for identifying AAV superimposed on RA. METHODS: Patients with both AAV and RA were identified by searching our hospital database and the literature. Data including age, sex, clinical manifestation, laboratory tests, renal pathology, and therapeutic regimens were retrieved. To assess the difference in clinical features and renal pathology between AAV patients with and without RA, we conducted 1:4 matched case-control studies. RESULTS: A total of 47 patients were identified, 15 from our hospital and 32 from the literature, and 33 (70.2%) were women. AAV was diagnosed later than RA in 83.0% of the patients and manifested as microscopic polyangiitis (MPA) in 78.7% of the patients. The kidney was the most frequently involved extra-articular organ (74.5%), followed by the lung (51.1%), and skin (8.5%). Patients with both AAV and RA were more likely to be asymptomatic (26.7% vs 3.3%, p = 0.013) than those with isolated AAV. However, they did not differ in other clinicopathological features. In RA patients, those with ANCA associated glomerulonephritis, were more likely to have decreased renal function at renal biopsy as opposed to those with primary glomerulonephritis. CONCLUSIONS: AAV can coexist with RA. In this coexistence, AAV usually develops after RA, is more likely to be asymptomatic, and manifests predominately as MPA with renal involvement. Thus, we should remain vigilant to superimposed AAV on RA.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Artritis Reumatoide , Glomerulonefritis , Poliangitis Microscópica , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/diagnóstico , Anticuerpos Anticitoplasma de Neutrófilos , Artritis Reumatoide/complicaciones , Femenino , Glomerulonefritis/complicaciones , Humanos , Masculino , Poliangitis Microscópica/complicaciones , Estudios Retrospectivos
11.
Br J Neurosurg ; 36(6): 693-698, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35393907

RESUMEN

BACKGROUND: Mechanical obstruction is the most common cause of shunt failure for hydrocephalic patients. However, the diagnosis is extremely challenging and often requires invasive testing methods. Thus, a simple and non-invasive technique is in urgent need to predict the intracranial pressure (ICP) of hydrocephalic patients during their post-surgical follow-up, which could help neurosurgeons to determine the conditions of the shunt system. MATERIALS AND METHODS: Two groups of patients were enrolled in the current study. In group I, patients were enrolled as they were diagnosed with high ICP hydrocephalus and received shunt surgery. The shunt valve pressures were taken for their post-surgical ICP. Meanwhile, the participants of group II exhibited abnormally increased lumbar puncture opening pressure (LPOP; from 180 to 400 mmH2O). Both the ICP and LPOP were used to match with their corresponding tympanic membrane temperature (TMT). RESULTS: When patients' ICP were in the normal range (group I, from 50 to 180 mmH2O), the TMT correlated with ICP in a linear regression model (R2 = 0.59, p < 0.001). Interestingly, when patients exhibited above-normal ICP (LPOP was from 180 to 400 mmH2O), their TMT fit well with the ICP in a third-order polynomial regression (R2 = 0.88). When the ICP was 287.98 mmH2O, the TMT approached the vertex, which was 38.54 °C. Based on this TMT-ICP algorithm, we invented a non-invasive ICP monitor system. Interestingly, a tight linear correlation was detected between the ICP data drawn from the non-invasive device and Codman ICP monitoring system (R2 = 0.93, p < 0.01). CONCLUSIONS: We believe the TMT-ICP algorithm (the Y-Jiang model) could be used for preliminary prediction of shunt malfunction as well as monitoring ICP changes.


Asunto(s)
Hidrocefalia , Presión Intracraneal , Humanos , Invenciones , Hidrocefalia/diagnóstico , Hidrocefalia/cirugía , Monitoreo Fisiológico , Derivaciones del Líquido Cefalorraquídeo
12.
J Am Chem Soc ; 143(38): 15723-15731, 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34520199

RESUMEN

Selenium-containing polymers are a group of fascinating functional polymers with unique structures, properties, and applications, which have been developed recently but only with limited examples. The challenges of developing selenium-containing polymers with structural and functional diversity include the lack of economic and safe monomers, lack of efficient and convenient synthetic approaches, and poor stability of selenium-involving covalent bonds. In this work, room-temperature metal-free multicomponent polymerizations (MCPs) of elemental selenium, diisocyanides, and dipropargyl alcohols were developed, and polymers with a selenium-containing aliphatic heterocycle, 1,3-oxaselenolane, were synthesized through these MCPs directly from elemental selenium. The alicyclic poly(oxaselenolane)s enjoyed high yields (up to 93%), high molecular weights (up to 15 600 g/mol), high thermal and chemical stability, good solubility and processability. With the structural design of the poly(oxaselenolane)s and their high selenium contents of up to 33.7 wt %, the refractive indices of their spin-coated thin films could reach 1.8026 at 633 nm and maintain 1.7770 at 1700 nm. It is anticipated that these efficient, convenient, mild, and economic multicomponent polymerizations of elemental selenium can promote the selenium-related polymer chemistry and accelerate the exploration of diversified selenium-containing functional polymer materials.

13.
Macromol Rapid Commun ; 42(6): e2000633, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33314555

RESUMEN

Multicomponent polymerizations (MCPs) are a group of fascinating polymer synthesis approaches that are developed rapidly in the recent decade. As a popular alkyne-based MCP, the A3 -polycouplings of alkynes, aldehydes, and amines are developed for the synthesis of poly(propargylamine)s under the catalysis of metal catalysts. In this work, through the design of carboxylic acid group-activated alkyne monomers, a catalyst-free, four-component polymerization of propiolic acids, benzylamines, organoboronic acids, and formaldehyde is reported under mild condition at 45 °C in dichloroethane. This four-component polymerization is applicable to different monomer structures, which can afford seven poly(propargylamine)s with up to 94% yields and molecular weights of up to 13 900 g mol-1 . Moreover, the poly(propargylamine)s demonstrate good solubility and processibility, high thermal stability and light refractivity, unique photophysical property, and so on. The simple monomers, mild condition, low cost, high efficiency, and procedure simplicity of this catalyst-free four-component polymerization demonstrates an elegant example of functional polymer synthesis.


Asunto(s)
Alquinos , Bencilaminas , Catálisis , Formaldehído , Pargilina/análogos & derivados , Polimerizacion , Propilaminas
14.
BMC Ophthalmol ; 21(1): 20, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413216

RESUMEN

BACKGROUND: Implantation of the posterior chamber phakic intraocular lens has been widely performed to correct high and extreme myopia. Chronic intraocular pressure (IOP) elevation may occur in its late postoperative period. For medically uncontrolled cases, surgical treatment is necessary, and benefits should be weighed against risks when determining whether to remove the lens. CASE PRESENTATION: A 32-year-old man with extremely high myopia presented with progressive blurred vision and medically uncontrolled IOP in the right eye. His past ocular history was significant for bilateral implantable collamer lens (ICL) implantation ten years ago. On ophthalmic examination, the ICL was well placed with a vault height of 456 µm in the right eye. The anterior chamber angles were open but narrow, and mild to moderate trabecular pigmentation was noted. Ex-PRESS glaucoma filtration surgery without ICL removal was performed to control IOP. During surgery, an Ex-PRESS P50 shunt was inserted into the anterior chamber via the front edge of the blue-grey transition zone between the sclera and cornea. Transient hypotony and shallow anterior chamber occurred in the first week after surgery, along with an ICL tilt towards the cornea with reduced vault height. No other complications related to either the ICL or the Ex-PRESS shunt were noted. IOP remained stable at 12 ~ 14 mmHg at the first 3-month follow-up. CONCLUSIONS: Ex-PRESS glaucoma filtration surgery might be a safe and effective alternative treatment for intractable glaucoma with high myopia and ICL implantation. Careful assessment of the ICL position and anterior chamber angle is necessary to plan the appropriate surgical procedure. A postoperative shallow anterior chamber may result in ICL dislocation.


Asunto(s)
Glaucoma , Miopía , Lentes Intraoculares Fáquicas , Adulto , Glaucoma/cirugía , Humanos , Presión Intraocular , Implantación de Lentes Intraoculares , Masculino , Miopía/cirugía
15.
J Am Chem Soc ; 142(2): 978-986, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31841620

RESUMEN

Sulfur utilization is a global concern because of its abundant nature sources and the safety or environmental problems caused by its burning or oxidation during storage, while sulfur-containing polymers are popular materials in virtue of their fascinating properties such as metal coordination ability, high refractive indices, and semiconducting property. The synthesis of sulfur-containing polymers is challenging, especially directly from elemental sulfur. Herein, catalyst-free and scalable multicomponent polymerizations (MCPs) of all commercially available elemental sulfur, dicarboxylic acids, and diamines were reported to facilely construct 12 polythioamides with diverse and well-defined structures, high molecular weights (Mw's up to 86 200 g/mol), and excellent yields (up to 99%) from elemental sulfur. Besides commonly used aliphatic diamines, aromatic diamine monomers are also applicable to these multicomponent polymerizations, affording polythioamides with unique rigid structures and improved functionality as compared to those of the previously reported polythioamides. These polythioamides can be applied in gold recovery, which could extract a trace amount of Au3+ from practical acidic leaching solution of discarded electronic waste selectively, rapidly (1 min), sensitively (10 ppb), and efficiently (>99.99%) with high extraction capacity up to 0.60 g· Au3+/g to directly afford high-purity elemental gold after pyrolysis. The MCPs could make use of both abundantly existing sulfur waste and trace amounts of precious gold residue in electronic wastes, demonstrating their great potential in resource utilization.

16.
Small ; 16(8): e1907074, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32003921

RESUMEN

Organic microlasers have attracted much attention due to their unique features such as high mechanical flexibility, facile doping of gain materials, high optical quality, simplicity and low-cost fabrication. However, organic gain materials usually suffer from aggregation-caused quenching (ACQ), preventing further advances of organic microlasers. Here, a new type of microlaser from aggregation-induced emission (AIE) material is successfully demonstrated. By introducing a typical noncrystalline AIE material, a high quality microlaser is obtained via a surface tension-induced self-assembly approach. Distinct from conventional organic microlasers, the organic luminescent material used here is initially nonluminescent but can shine after aggregation under optical pumping. Further investigations demonstrate that AIE-based microlasers exhibit advantages to enable much higher doping concentrations, which provides an alternative way to improved lasing performance including dramatically reduced threshold and favorable lasing stability. It is believed that these results could provide a promising way to extend the content of microlasers and open a new avenue to enable applications ranging from chemical sensing to biology.

17.
Acta Pharmacol Sin ; 40(5): 583-588, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30224637

RESUMEN

Increasing preclinical evidence demonstrates that dopamine D3 receptor (D3R) antagonists are a potential option for the treatment of drug addiction. The reinstatement of the addiction can be triggered by environmental stimuli that acquire motivational salience through repeated associations with the drug's effects. YQA14 is a novel D3R antagonist that has exhibited pharmacotherapeutic efficacy in reducing cocaine and amphetamine reward and relapse to drug seeking in mice. In this study we investigated the effects of YQA14 on morphine-induced context-specific locomotor sensitization in mice. We showed that repeated injection of YQA14 (6.25-25 mg/kg every day ip) prior to morphine (10 mg/kg every day sc) not only inhibited the acquisition, but also significantly attenuated the expression of morphine-induced locomotor sensitization. Furthermore, in the expression phase, one single injection of YQA14 (6.25-25 mg/kg, ip) dose-dependently inhibited the expression of morphine-induced behavioral sensitization. Moreover, YQA14 inhibited the expression of morphine-induced behavioral sensitization in wild mice (WT), but not in D3R knockout (D3R-/-) mice in the expression phase. In addition, D3R-/- mice also displayed the reduction in the expression phase compared with WT mice. In summary, this study demonstrates that blockade or knockout of the D3R inhibits morphine-induced behavior sensitization, suggesting that D3R plays an important role in the pathogenesis and etiology of morphine addiction, and it might be a potential target for clinical management of opioid addiction.


Asunto(s)
Benzoxazoles/uso terapéutico , Antagonistas de Dopamina/uso terapéutico , Dependencia de Morfina/prevención & control , Morfina/farmacología , Actividad Motora/efectos de los fármacos , Piperazinas/uso terapéutico , Receptores de Dopamina D3/antagonistas & inhibidores , Animales , Benzoxazoles/administración & dosificación , Benzoxazoles/farmacocinética , Antagonistas de Dopamina/administración & dosificación , Antagonistas de Dopamina/farmacocinética , Comportamiento de Búsqueda de Drogas , Inyecciones Intraperitoneales , Masculino , Ratones Noqueados , Morfina/administración & dosificación , Dependencia de Morfina/etiología , Dependencia de Morfina/psicología , Piperazinas/administración & dosificación , Piperazinas/farmacocinética , Receptores de Dopamina D3/genética
18.
J Am Chem Soc ; 140(19): 6156-6163, 2018 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-29685036

RESUMEN

The utilization of sulfur is a global concern, considering the abundant and cheap source of sulfur from nature and petroleum industry, its limited consumption, and the safety/environmental problems caused during storage. The economic and efficient transformation of sulfur remains to be a great challenge for both academia and industry. Herein, a room temperature conversion from sulfur to functional polythioureas was reported through a catalyst-free multicomponent polymerization of sulfur, aliphatic diamines, and diisocyanides in air with 100% atom economy. The polymerization enjoys quick reaction and wide monomer scope, which affords 16 polythioureas with well-defined structures, high molecular weights ( Mws up to 242 500 g/mol), and excellent yields (up to 95%). The polythioureas can be utilized to detect mercury pollution with high sensitivity ( Ksv = 224 900 L/mol) and high selectivity, clean Hg2+ with high removal efficiency (>99.99%) to achieve drinking water standard, and monitor the real-time removal process by fluorescence.

19.
J Org Chem ; 83(17): 10453-10464, 2018 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-30102536

RESUMEN

A new transition-metal-free version for the synthesis of π-conjugated quinazoline-substituted ethene derivatives from readily available starting materials has been developed. Quinazoline-substituted ethenes were obtained in moderate to high yields with completely Z-selectivity, and the resulting quinazoline-substituted ethenes show typical aggregation-induced emission (AIE) properties.

20.
J Am Chem Soc ; 139(14): 5075-5084, 2017 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-28318273

RESUMEN

Sequence-controlled polymers, including biopolymers such as DNA, RNA, and proteins, have attracted much attention recently because of their sequence-dependent functionalities. The development of an efficient synthetic approach for non-natural sequence-controlled polymers is hence of great importance. Multicomponent polymerizations (MCPs) as a powerful and popular synthetic approach for functional polymers with great structural diversity have been demonstrated to be a promising tool for the synthesis of sequence-controlled polymers. In this work, we developed a facile metal-free one-pot multicomponent tandem polymerization (MCTP) of activated internal alkynes, aromatic diamines, and formaldehyde to successfully synthesize structural-regulated and sequence-controlled polyheterocycles with high molecular weights (up to 69 800 g/mol) in high yields (up to 99%). Through such MCTP, polymers with the in situ generated multisubstituted tetrahydropyrimidines or dihydropyrrolones in the backbone and inherent luminescence can be easily obtained with high atom economy and environmental benefit, which is inaccessible by other synthetic approaches.

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