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1.
Proc Natl Acad Sci U S A ; 119(34): e2203346119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35969757

RESUMEN

Plastic waste represents one of the most urgent environmental challenges facing humankind. Upcycling has been proposed to solve the low profitability and high market sensitivity of known recycling methods. Existing upcycling methods operate under energy-intense conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. Herein, we report a tandem degradation-upcycling strategy to exploit high-value chemicals from polystyrene (PS) waste with high selectivity. We first degrade PS waste to aromatics using ultraviolet (UV) light and then valorize the intermediate to diphenylmethane. Low-cost AlCl3 catalyzes both the reactions of degradation and upcycling at ambient temperatures under atmospheric pressure. The degraded intermediates can advantageously serve as solvents for processing the solid plastic wastes, forming a self-sustainable circuitry. The low-value-input and high-value-output approach is thus substantially more sustainable and economically viable than conventional thermal processes, which operate at high-temperature, high-pressure conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. The cascade strategy is resilient to impurities from plastic waste streams and is generalizable to other high-value chemicals (e.g., benzophenone, 1,2-diphenylethane, and 4-phenyl-4-oxo butyric acid). The upcycling to diphenylmethane was tested at 1-kg laboratory scale and attested by industrial-scale techno-economic analysis, demonstrating sustainability and economic viability without government subsidies or tax credits.


Asunto(s)
Poliestirenos , Reciclaje , Eliminación de Residuos , Plásticos/síntesis química , Poliestirenos/química , Eliminación de Residuos/métodos , Solventes
2.
Genomics ; 116(1): 110779, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38168627

RESUMEN

Meat quality is a critical aspect of pig breeding. In addition to genetics, meat quality is also influenced by nutritional and environmental factors. In this study, three pig breeds, Shengxianhua, Jiaxing, and Qinglian Black (SXH, JXB and QLB), were used as experimental animals. Transcriptional analysis was performed on the longissimus thoracis (LT) muscle to investigate variations in intramuscular fat (IMF), inosine monophosphate (IMP), amino acids, and muscle fiber morphology across different breeds. Ingenuity canonical pathway analysis (IPA) identified biological processes and key driver genes related to metabolism and muscle development. Additionally, weighted gene co-expression network analysis (WGCNA) revealed gene modules associated with IMP. KEGG and GO analyses identified specific biological processes and signaling pathways related to IMP, including the Oxidative Phosphorylation pathway and rRNA Metabolic Processes. These findings provide novel insights into the molecular regulatory mechanisms underlying meat quality variations among pig breeds.


Asunto(s)
Perfilación de la Expresión Génica , Músculo Esquelético , Porcinos/genética , Animales , Músculo Esquelético/metabolismo , Carne/análisis , Redes Reguladoras de Genes , Aminoácidos
3.
Small ; 20(27): e2310756, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38361223

RESUMEN

P2-phase layered cathodes play a pivotal role in sodium-ion batteries due to their efficient Na+ intercalation chemistry. However, limited by crystal disintegration and interfacial instability, bulk and interfacial failure plague their electrochemical performance. To address these challenges, a structural enhancement combined with surface modification is achieved through trace Y doping. Based on a synergistic combination of experimental results and density functional theory (DFT) calculations, the introduction of partial Y ions at the Na site (2d) acts as a stabilizing pillar, mitigating the electrostatic repulsions between adjacent TMO2 slabs and thereby relieving internal structural stress. Furthermore, the presence of Y effectively optimizes the Ni 3d-O 2p hybridization, resulting in enhanced electronic conductivity and a notable rapid charging ability, with a capacity of 77.3 mA h g-1 at 40 C. Concurrently, the introduction of Y also induces the formation of perovskite nano-islands, which serve to minimize side reactions and modulate interfacial diffusion. As a result, the refined P2-Na0.65 Y0.025[Ni0.33Mn0.67]O2 cathode material exhibits an exceptionally low volume variation (≈1.99%), an impressive capacity retention of 83.3% even at -40 °C after1500 cycles at 1 C.

4.
Int J Obes (Lond) ; 48(6): 849-858, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38341506

RESUMEN

OBJECTIVE: Fatty acids play a critical role in the proper functioning of the brain. This study investigated the effects of a high-fat (HF) diet on brain fatty acid profiles of offspring exposed to maternal gestational diabetes mellitus (GDM). METHODS: Insulin receptor antagonist (S961) and HF diet were used to establish the GDM animal model. Brain fatty acid profiles of the offspring mice were measured by gas chromatography at weaning and adulthood. Protein expressions of the fatty acid transport pathway Wnt3/ß-catenin and the target protein major facilitator superfamily domain-containing 2a (MFSD2a) were measured in the offspring brain by Western blot. RESULTS: Maternal GDM increased the body weight of male offspring (P < 0.05). In weaning offspring, factorial analysis showed that maternal GDM increased the monounsaturated fatty acid (MUFA) percentage of the weaning offspring's brain (P < 0.05). Maternal GDM decreased offspring brain arachidonic acid (AA), but HF diet increased brain linoleic acid (LA) (P < 0.05). Maternal GDM and HF diet reduced offspring brain docosahexaenoic acid (DHA), and the male offspring had higher DHA than the female offspring (P < 0.05). In adult offspring, factorial analysis showed that HF diet increased brain MUFA in offspring, and male offspring had higher brain MUFA than female offspring (P < 0.05). The HF diet increased brain LA in the offspring. Male offspring had higher level of AA than female offspring (P < 0.05). HF diet reduced DHA in the brains of female offspring. The brain protein expression of ß-catenin and MFSD2a in both weaning and adult female offspring was lower in the HF + GDM group than in the CON group (P < 0.05). CONCLUSIONS: Maternal GDM increased the susceptibility of male offspring to HF diet-induced obesity. HF diet-induced adverse brain fatty acid profiles in both male and female offspring exposed to GDM.


Asunto(s)
Encéfalo , Diabetes Gestacional , Dieta Alta en Grasa , Ácidos Grasos , Efectos Tardíos de la Exposición Prenatal , Animales , Embarazo , Femenino , Diabetes Gestacional/metabolismo , Ratones , Dieta Alta en Grasa/efectos adversos , Encéfalo/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Masculino , Ácidos Grasos/metabolismo , Modelos Animales de Enfermedad , Fenómenos Fisiologicos Nutricionales Maternos
5.
J Nutr ; 154(2): 590-599, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38159812

RESUMEN

BACKGROUND: Polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA), are critical for proper fetal brain growth and development. Gestational diabetes mellitus (GDM) could affect maternal-fetal fatty acid metabolism. OBJECTIVE: This study aimed to explore the effect of GDM and high-fat (HF) diet on the DHA transport signaling pathway in the placenta-brain axis and fatty acid concentrations in the fetal brain. METHODS: Insulin receptor antagonist (S961) and HF diet were used to establish an animal model of GDM. Eighty female C57BL/6J mice were randomly divided into control (CON), GDM, HF, and HF+GDM groups. The fatty acid profiles of the maternal liver and fetal brain were analyzed by gas chromatography. In addition, we analyzed the protein amounts of maternal liver fatty acid desaturase (FADS1/3), elongase (ELOVL2/5) and the regulatory factor sterol-regulatory element-binding protein (SREBP)-1c, and the DHA transport signaling pathway (Wnt3/ß-catenin/MFSD2a) of the placenta and fetal brain using western blotting. RESULTS: GDM promoted the decrease of maternal liver ELOVL2, ELOVL5, and SREBP-1c. Accordingly, we observed a significant decrease in the amount of maternal liver arachidonic acid (AA), DHA, and total n-3 PUFA and n-6 PUFA induced by GDM. GDM also significantly decreased the amount of DHA and n-3 PUFA in the fetal brain. GDM downregulated the Wnt3/ß-catenin/MFSD2a signaling pathway, which transfers n-3 PUFA in the placenta and fetal brain. The HF diet increased n-6 PUFA amounts in the maternal liver, correspondingly increasing linoleic acid, gamma-linolenic acid, AA, and total n-6 PUFA in the fetal brain, but decreased DHA amount in the fetal brain. However, HF diet only tended to decrease placental ß-catenin and MFSD2a amounts (P = 0.074 and P = 0.098, respectively). CONCLUSIONS: Maternal GDM could affect the fatty acid profile of the fetal brain both by downregulating the Wnt3/ß-catenin/MFSD2a pathway of the placental-fetal barrier and by affecting maternal fatty acid metabolism.


Asunto(s)
Diabetes Gestacional , Ácidos Grasos Omega-3 , Humanos , Animales , Ratones , Femenino , Embarazo , Diabetes Gestacional/metabolismo , Ácidos Grasos/metabolismo , Placenta/metabolismo , beta Catenina/metabolismo , Ratones Endogámicos C57BL , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Insaturados/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Ácido Araquidónico , Encéfalo/metabolismo
6.
Org Biomol Chem ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39290038

RESUMEN

The metal-free BF3-catalyzed hydroamination of silylynamides with amines allows facile and efficient synthesis of α-silylmethylamidines in moderate to excellent yields (up to 99%) with a broad substrate scope and excellent functional group compatibility under mild reaction conditions. This protocol offers the first synthetic route to silyl-incorporated amidine compounds, which features the use of Lewis acid BF3 as the catalyst and easily available silylynamides as the silicon source. Considering the biological importance of amidine scaffolds and silyl groups, the easy incorporation of these two structural units should make great sense for medicinal chemistry. Notably, with this strategy, the installation of amidine scaffolds to drug-like molecules celecoxib and estrone is realized for the first time. A plausible mechanism involves the formation of vinyl-boron intermediates from BF3-activated ynamides, which after protodeboronation and tautomerization afford the desired products.

7.
J Paediatr Child Health ; 60(8): 355-360, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39032105

RESUMEN

AIM: Surgery for congenital scoliosis correction in children is often associated with considerable blood loss. Decrease in regional oxygen saturation (rScO2) can reflect insufficient cerebral perfusion and predict neurological complications. This retrospective observational study explored the relationship between blood loss during this surgery and a decrease in rScO2 in children. METHODS: The following clinical data of children aged 3-14 years who underwent elective posterior scoliosis correction between March 2019 and July 2021 were collected: age, sex, height, weight, baseline rScO2, basal mean invasive arterial pressure (MAP), preoperative Cobb angle, number of surgical segments, preoperative and postoperative haemoglobin level, percentage of lowest rScO2 below the baseline value that lasted 3 min or more during the operation (decline of rScO2 from baseline, D-rScO2%), intraoperative average invasive MAP, end-tidal carbon dioxide pressure, fluid infusion rate of crystalloids and colloids, operation time, and percentage of total blood loss/patient's blood volume (TBL/PBV). RESULTS: A total of 105 children were included in the study. Massive haemorrhage (TBL/PBV ≥50%) was reported in 53.3% of patients, who had significantly higher D-rScO2 (%) (t = -5.264, P < 0.001) than those who had non-massive haemorrhage (TBL/PBV <50%). Multiple regression analysis revealed that TBL/PBV (ß = 0.04, 95% CI: 0.018-0.062, P < 0.05) was significantly associated with D-rScO2%. CONCLUSIONS: Intraoperative massive blood loss in children significantly increased D-rScO2%. Monitoring should be improved, and timely blood supplementation should be performed to ensure maintenance of the blood and oxygen supply to vital organs, improve the safety of anaesthesia, and avoid neurological complications.


Asunto(s)
Pérdida de Sangre Quirúrgica , Escoliosis , Humanos , Niño , Estudios Retrospectivos , Escoliosis/cirugía , Femenino , Masculino , Adolescente , Preescolar , Pérdida de Sangre Quirúrgica/prevención & control , Saturación de Oxígeno , Circulación Cerebrovascular/fisiología
8.
Molecules ; 29(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38257253

RESUMEN

A high phosphoric acid uptake and retention capacity are crucial for the high performance and stable operation of phosphoric acid/polybenzimidazole (PA/PBI)-based high-temperature proton exchange membranes. In this work, amine end-functionalized side-chain grafted PBI (AGPBI) with different grafting degrees are synthesized to enhance both the phosphoric acid uptake and the acid retention ability of the accordingly formed membranes. The optimized acid-base membrane exhibits a PA uptake of 374.4% and an anhydrous proton conductivity of 0.067 S cm-1 at 160 °C, with the remaining proton conductivity percentages of 91.0% after a 100 h stability test. The accordingly fabricated membrane electrode assembly deliver peak power densities of 0.407 and 0.638 W cm-2 under backpressure of 0 and 200 kPa, which are significantly higher than 0.305 and 0.477 W cm-2 for the phosphoric acid-doped unmodified PBI membrane under the same conditions.

9.
Small ; 19(10): e2206437, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36564366

RESUMEN

The desire for exploration of cellular functional mechanisms has substantially increased the rapid development of artificial cells. However, the construction of synthetic cells with high organizational complexity remains challenging due to the lack of facile approaches ensuring dynamic multi-compartments of cytoplasm and stability of membranes in protocells. Herein, a stable coacervate-in-Pickering emulsion protocell model comprising a membraneless coacervate phase formed by poly-l-lysine (PLys) and adenosine triphosphate (ATP) encapsulated in Pickering emulsion is put forward only through simple one-step emulsification. The dynamic distribution of intracellular components (coacervates in this protocell model) can be manipulated by changes in temperature or pH. This coacervate-in-Pickering emulsion protocell system exhibits repeatable cycle stability in response to external stimuli (at least 24 cycles for temperature and 3 cycles for pH). By encapsulating antagonistic enzymes into coacervates, glucose oxidase (GOx) and urease as an example, the control of local enzyme concentration is achieved by introducing glucose and urea to adjust the pH value in Pickering emulsion droplets. This hybrid protocell model with programmatically dynamic microcompartmentation and sufficient stability is expected to be further studied and applied in cellular biology, facilitating the development of lifelike systems with potential in practical applications.


Asunto(s)
Células Artificiales , Emulsiones , Glucosa Oxidasa , Adenosina Trifosfato , Ureasa
10.
Cell Biol Int ; 47(7): 1161-1169, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37092585

RESUMEN

Many indicators, including red cell distribution width (RDW) and iron metabolism, are sensitive to a variety of risk factors, and are associated with the pathological alterations and disease onset. RDW reflects the degree of heterogeneous volumes of peripheral red blood cells (RBCs). It has been well-known that increased RDW indicates iron deficiency anemia, hemolytic anemia, ineffective erythropoiesis, and shorten lifespan of RBCs. Increased RDW is also prevalent in various non-anemic pathological conditions and diseases. We here review the factors affecting RDW, particularly disordered iron metabolism, chronic inflammation, and oxidative stress, and recapitulate the interplays among these factors. Furthermore, we review the application of increased RDW together with disordered iron homeostasis and the deregulations of hepcidin expression and ferritin levels in the diagnoses and prognosis of anemic and nonanemic diseases. RDW is inexpensive and readily available and may be valuable in adding to the diagnosis and monitoring of many pathological conditions. RDW combined with other indicators, for example, hepcidin and ferritin levels, should be utilized more frequently in clinical practice.


Asunto(s)
Índices de Eritrocitos , Hepcidinas , Hepcidinas/metabolismo , Eritrocitos/metabolismo , Hierro/metabolismo , Ferritinas/metabolismo
11.
Inorg Chem ; 62(22): 8655-8662, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37222000

RESUMEN

Heterogeneous solid base catalysts are highly expected due to their high activity and environmentally friendly nature in a variety of reactions. However, the catalytic activity of traditional solid base catalysts is controlled by external factors (such as temperature and pressure), and regulation of the activity by in situ changing their own properties has never been reported. Herein, we report a smart solid base catalyst by chemically anchoring the photoresponsive azobenzene derivative p-phenylazobenzoyl chloride (PAC) onto the metal-organic framework UiO-66-NH2 (UN) for the first time, which can regulate the catalytic activity through remote control of external light. The prepared catalysts have a regular crystal structure and photoresponsive properties. It is fascinating that the configuration of PAC can be isomerized easily during UV- and visible-light irradiation and resulted in regulation of the catalytic activity. In the Knoevenagel condensation of 1-naphthaldehyde and ethyl cyanoacetate to ethyl 2-cyano-3-(1-naphthalenyl)acrylate, the optimal catalyst shows up to 56.2% of change after trans/cis isomerization, while the change of the yield over UN is negligible. The regulated catalytic behavior can be assigned to the steric hindrance change of the catalysts under external light irradiation. This work may shed light on the design and construction of smart solid base catalysts with tailorable properties for various reactions.

12.
Environ Sci Technol ; 57(21): 7924-7937, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37184982

RESUMEN

Although PM2.5 (fine particles with aerodynamic diameter <2.5 µm) exposure shows the potential to impact normal hematopoiesis, the detailed alterations in systemic hematopoiesis and the underlying mechanisms remain unclear. For hematopoiesis under steady-state or stress conditions, nuclear factor erythroid 2-related factor 2 (NRF2) is essential for regulating hematopoietic processes to maintain blood homeostasis. Herein, we characterized changes in the populations of hematopoietic stem progenitor cells and committed hematopoietic progenitors in the lungs and bone marrow (BM) of wild-type and Nrf2-/- C57BL/6J male mice. PM2.5-induced NRF2-dependent biased hematopoiesis toward myeloid lineage in the lungs and BM generates excessive numbers of various inflammatory immune cells, including neutrophils, monocytes, and platelets. The increased population of these immune cells in the lungs, BM, and peripheral blood has been associated with observed pulmonary fibrosis and high disease risks in an NRF2-dependent manner. Therefore, although NRF2 is a protective factor against stressors, upon PM2.5 exposure, NRF2 is involved in stress myelopoiesis and enhanced PM2.5 toxicity in pulmonary injury, even leading to systemic inflammation.


Asunto(s)
Hematopoyesis , Factor 2 Relacionado con NF-E2 , Ratones , Masculino , Animales , Ratones Endogámicos C57BL , Hematopoyesis/fisiología , Células Madre Hematopoyéticas , Material Particulado/toxicidad
13.
Angew Chem Int Ed Engl ; 62(36): e202307042, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37439282

RESUMEN

Polystyrene (PS) is one of the least recycled large-volume commodity plastics due to bulkiness of foam products and associated contaminants. PS recycling is also severely hampered by the lack of financial incentive, limited versatility, and poor selectivity of existing methods. To this end, herein we report a thermochemical recycling strategy of "degradation-upcycling" to synthesize a library of high-value aromatic chemicals from PS wastes with high versatility and selectivity. Two cascade reactions are selected to first degrade PS to benzene under mild temperatures, followed by the derivatization thereof utilizing a variety of acyl/alkyl and sulfinyl chloride additives. To demonstrate the versatility, nine ketones and sulfides of cosmetic and pharmaceutical relevance were prepared, including propiophenone, benzophenone, and diphenyl sulfide. The approach is also amenable to sophisticated upcycling reaction designs and can produce desired products stepwise. The facile and versatile approach will provide a scalable and profitable methodology for upcycling PS waste into value-added chemicals.

14.
Angew Chem Int Ed Engl ; 62(21): e202301739, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36932036

RESUMEN

Stimuli-responsive porous materials have captured much attention due to the on-demand tunable properties. Most reported stimuli-responsive porous materials are based on molecule isomerism or host-guest interaction, and it is highly desired to develop new types based on different responsive mechanism. Herein, inspired by natural cells which have the ability to fuse and divide induced by external stimulation, we report a new type of stimuli-responsive porous material based on detachment mechanism. A detachable porous organic polymer, namely DT-POP-1, is fabricated from the polymerization of anthracene-containing monomer (AnMon) when irradiated by 365 nm UV light. DT-POP-1 can detach into the monomer AnMon when irradiated with 275 nm UV light or heat. Such polymerization/detachment is reversible. The detachment results in a big difference in porosity and adsorption capacity, making the present detachable porous polymer highly promising in adsorptive separation and drug delivery.

15.
BMC Gastroenterol ; 22(1): 115, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35272624

RESUMEN

BACKGROUND: Undifferentiated pleomorphic sarcoma (UPS), also known as malignant fibrous histiocytoma (MFH), hardly originates from the colorectum. CASE PRESENTATION: We reported a 65-year-old female presented with UPS in the descending colon. Computed tomography (CT) revealed an irregularly thickened descending colon. On colonoscopy examination, an ulcerative tumour was identified. The patient received radical resection of the left colon and partial enterectomy. The resected tumor was ulcerative, 10 cm × 8 cm × 5 cm in size, and infiltrated the serosa layer. Postsurgical pathology showed that the tumor was high-graded UPS in the colon with large amounts of necrotic tissues. CONCLUSIONS: UPS in the large intestine is a rare malignant tumor with a poor prognosis and unknown pathogenesis. The main treatment for UPS is early complete resection. Postsurgery adjuvant radiotherapy or chemotherapy can be attempted.


Asunto(s)
Histiocitoma Fibroso Maligno , Sarcoma , Anciano , Colon/patología , Femenino , Histiocitoma Fibroso Maligno/diagnóstico por imagen , Histiocitoma Fibroso Maligno/cirugía , Humanos , Sarcoma/diagnóstico por imagen , Sarcoma/cirugía , Tomografía Computarizada por Rayos X
16.
Anal Chem ; 93(48): 16025-16034, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34817158

RESUMEN

Herein, we demonstrate that a new multicolor silver nanoclusters/graphene oxide (Ag NCs/GO) hybrid material, upon target response, undergoes a configuration transformation, based on entropy-driven enzyme-free toehold-mediated strand displacement reaction, achieving emission shift and enhancement. To realize the aim above, two different synthesis routes (route I and II) of synthesizing fluorescent Ag NCs for constructing toehold displacement Ag NCs/GO biosensor is designed and performed. Influenza A virus subtype genes (H1N1 and H5N1) as a model can efficiently initiate the operation of entropy-driven displacement reaction, resulting in activatable fluorescence. Red-emitting and green-emitting Ag NCs tethering the complementary sequence of H1N1 (pDNA1) and H5N1 (pDNA2) are indirectly immobilized on GO surface through binding with capture DNA (cDNA1 and cDNA2), respectively, forming multicolor pDNA-Ag NCs/GO nanohybrid materials. However, they do not exhibit nearly fluorescence signals attributed to energy transfer from donor Ag NCs to acceptor GO. Upon adding targets H1N1 and H5N1 (tDNA1 and tDNA2), pDNA1-Ag NCs and pDNA2-Ag NCs detach from GO, based on toehold-mediated strand displacement reaction, which interferes the energy transfer and leads to significant fluorescence enhancement. More interestingly, the activatable process is accompanied by remarkable hypsochromic shift (19 nm) or bathochromic shift (21 nm) emission with quite high fluorescence recovery rates (823.35% and 693.62%). Therefore, based on these phenomena, a novel multiple approach has been developed with the assistance of toehold displacement and Ag NCs/GO nanohybrid materials. As for the remarkable emission recovery and multichannel signal, the proposed approach displays the promising application prospect in accurate diagnosis and treatment.


Asunto(s)
Técnicas Biosensibles , Subtipo H1N1 del Virus de la Influenza A , Subtipo H5N1 del Virus de la Influenza A , Nanopartículas del Metal , ADN , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/genética , Plata
17.
Anal Chem ; 93(23): 8326-8335, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34076403

RESUMEN

In this work, we demonstrate that the emission wavelength and intensity of silver nanoclusters (Ag NCs) can be facilely tuned by the configuration transformation from the adsorption of Ag NCs to the graphene oxide (GO) surface to the desorption of Ag NCs from GO. Bicolor Ag NCs tethering the complementary sequence of influenza A virus genes are prepared, named green-emitting G-Ag NCs-CH5N1 (530 nm) and red-emitting R-Ag NCs-CH1N1 (589 nm). As for the high affinity of the complementary fragment of genes to GO, the adsorption of Ag NCs to GO leads to the formation of G-Ag NCs-CH5N1/GO and R-Ag NCs-CH1N1/GO nanocomposites, leading to fluorescent quenching due to energy transfer. By conjugating complementary sequences as capturing probes for targets, the formation of genes/Ag NC duplex-stranded structures results in the desorption of Ag NCs from GO, activating the fluorescence signal. More interestingly, compared with sole single-stranded DNA-templated fluorescent Ag NCs (ssDNA-Ag NCs), the activatable emission wavelength of the G-Ag NCs-CH5N1/H5N1 complex exhibits a notable red shift (555 nm) with a 49% recovery rate, while that of the R-Ag NCs-CH1N1/H1N1 complex shows a distinct blue shift (569 nm) with a 200% recovery rate. Via target-responsive configuration transformation of Ag NCs/GO hybrid materials, the emission wavelength and intensity of Ag NCs are effectively regulated. Based on the output changes according to different input combinations, novel dual-channel logic gates for multiplex simultaneous detection are developed by using the tunable color and intensity of ssDNA-Ag NCs. Our observation may open a new path for multiplex analysis in a facile and rapid way combining the logic gate strategy.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Subtipo H5N1 del Virus de la Influenza A , Nanopartículas del Metal , Nanocompuestos , ADN , ADN de Cadena Simple , Grafito , Subtipo H5N1 del Virus de la Influenza A/genética , Plata
18.
J Am Chem Soc ; 142(20): 9158-9162, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32392041

RESUMEN

The plasmonic properties of silver nanoparticle (AgNP) arrays are directly controlled by AgNP size, shape, and spatial arrangement. Reported here is a strategy to prepare chiral AgNP arrays templated by two constitutionally isomeric aromatic peptide amphiphiles (APAs), KSC'EKS and C'EKSKS (KS = S-aroylthiooxime-modified lysine, C' = citrulline, and E = glutamic acid). In phosphate buffer, both APAs initially self-assembled into nanoribbons with a similar geometry. However, in the presence of silver ions and poly(sodium 4-styrenesulfonate) (PSSS), one of the nanoribbons (KSC'EKS) turned into nanohelices with a regular twisting pitch, while the other (C'EKSKS) remained as nanoribbons. Both were used as templates for synthesis of arrays of ∼8 nm AgNPs to understand how small changes in molecular structure affect the plasmonic properties of these chiral AgNP/APA hybrids. Both hybrids showed improved colloidal stability compared to pure AgNPs, and both showed enhanced sensitivity as surface-enhanced Raman spectroscopy (SERS) substrates for model analytes, with nanohelices showing better SERS performance compared to their nanoribbon counterparts and pure AgNPs.


Asunto(s)
Nanopartículas del Metal/química , Péptidos/síntesis química , Plata/química , Estructura Molecular , Tamaño de la Partícula , Péptidos/química , Propiedades de Superficie
19.
Exp Cell Res ; 374(2): 274-281, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30352219

RESUMEN

COP9 signalosome subunit 5 (CSN5) has been involved in the progression of diverse human cancers. MMP2 plays an important role in the metastasis of cancer cells. However, the roles and relationship of in pancreatic cancer (PC) is still unknown. Here, our data shown that both CSN5 and MMP2 were significantly upregulated in PC compared with the corresponding adjacent tissues, where a positive correlation in their expression and associated malignant characteristics were found. Further, silencing of CSN5 expression markedly inhibited PC invasion and metastasis in vitro and in vivo, accompanied by decreased MMP2 expression. Moreover, the anti-metastasis role of CSN5 silence was reversed by MMP2 overexpression, whereas knockdown of MMP2 decreased PC metastasis driven by upregulation of CSN5. Further investigation revealed that CSN5 regulated MMP2 expression via activation of FOXM1 in PC cells. Mechanistically, CSN5 directly bound FOXM1 and decreased its ubiquitination to enhance the protein stability of FOXM1. Taken together, the results indicate that CSN5 can contribute to PC invasion and metastasis through activation of FOXM1/MMP2 axis.


Asunto(s)
Complejo del Señalosoma COP9/genética , Proteína Forkhead Box M1/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Invasividad Neoplásica/genética , Metástasis de la Neoplasia/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Péptido Hidrolasas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Metaloproteinasa 2 de la Matriz/genética , Invasividad Neoplásica/patología , Metástasis de la Neoplasia/patología , Células PC-3 , Transducción de Señal/genética , Ubiquitinación/genética , Regulación hacia Arriba/genética
20.
Environ Res ; 190: 109931, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32781323

RESUMEN

Removal of toxic aniline from wastewater is of great importance in industrial manufacture. Traditional electrochemical methods encounter obstacles such as high energy consumption in mineralization and severe electrode passivation in electro-polymerization. In this paper, we report a practical electro-polymerization method by using Ti/Sb-SnO2/PbO2 anode to treat high concentration aniline wastewater. The cyclic voltammetric experiment was conducted and the problem of electrode passivation was solved by increasing the electrode potential. In the experiments of treating aniline wastewater, the produced solid polymer can separate from water rather than sticking to electrode surface. Elemental analysis shows that oxygen is incorporated in the polymer. Experiments were conducted under different conditions, including current density, pH and initial concentration of aniline and Na2SO4. The electro-polymerization route accounts for nearly 50% contribution in the removal of chemical oxygen demand (COD). Our electro-polymerization method gives an apparent current efficiency (ACE) of 232.15% and an energy consumption (Ep) of 0.008658 kWh g-1COD-1 when half of COD is removed at a current density of 15 mA cm-2, pH of 7.0, initial aniline concentration of 1.2 g L-1 and Na2SO4 concentration of 4 g L.-1.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Compuestos de Anilina , Electroquímica , Oxidación-Reducción , Polimerizacion , Eliminación de Residuos Líquidos , Aguas Residuales
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