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1.
Gastroenterology ; 163(5): 1267-1280.e7, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35718227

RESUMEN

BACKGROUND & AIMS: The stroma in pancreatic ductal adenocarcinoma (PDAC) contributes to its immunosuppressive nature and therapeutic resistance. Herein we sought to modify signaling and enhance immunotherapy efficacy by targeting multiple stromal components through both intracellular and extracellular mechanisms. METHODS: A murine liver metastasis syngeneic model of PDAC was treated with focal adhesion kinase inhibitor (FAKi), anti-programmed cell death protein 1 (PD-1) antibody, and stromal hyaluronan (HA) degradation by PEGylated recombinant human hyaluronidase (PEGPH20) to assess immune and stromal modulating effects of these agents and their combinations. RESULTS: The results showed that HA degradation by PEGPH20 and reduction in phosphorylated FAK expression by FAKi leads to improved survival in PDAC-bearing mice treated with anti-PD-1 antibody. HA degradation in combination with FAKi and anti-PD-1 antibody increases T-cell infiltration and alters T-cell phenotype toward effector memory T cells. FAKi alters the expression of T-cell modulating cytokines and leads to changes in T-cell metabolism and increases in effector T-cell signatures. HA degradation in combination with anti-PD-1 antibody and FAKi treatments reduces granulocytes, including granulocytic- myeloid-derived suppressor cells and decreases C-X-C chemokine receptor type 4 (CXCR4)-expressing myeloid cells, particularly the CXCR4-expressing granulocytes. Anti-CXCR4 antibody combined with FAKi and anti-PD-1 antibody significantly decreases metastatic rates in the PDAC liver metastasis model. CONCLUSIONS: This represents the first preclinical study to identify synergistic effects of targeting both intracellular and extracellular components within the PDAC stroma and supports testing anti-CXCR4 antibody in combination with FAKi as a PDAC treatment strategy.


Asunto(s)
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Ratones , Animales , Neoplasias Pancreáticas/patología , Adenocarcinoma/patología , Hialuronoglucosaminidasa/farmacología , Hialuronoglucosaminidasa/uso terapéutico , Ácido Hialurónico , Carcinoma Ductal Pancreático/genética , Neoplasias Hepáticas/tratamiento farmacológico , Proteína-Tirosina Quinasas de Adhesión Focal , Citocinas/farmacología , Muerte Celular , Polietilenglicoles/uso terapéutico , Microambiente Tumoral , Neoplasias Pancreáticas
2.
Nano Lett ; 22(11): 4354-4361, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35611952

RESUMEN

Particulate matter damages engines of vehicles when blown into the ventilation system. Conventional engine-intake filter is cellulose microfiber board with an average diameter larger than ten microns, which has low removal efficiency of ultrafine particular matter. In this work, we apply ultrafine polyurethane nanofibers (∼122.8 nm) onto pleated cellulose board using scalable multinozzle electroblow spinning technology, which improves filtration efficiency of particulate matter with a diameter of less than 0.3 µm PM0.3 greatly. The thermoplastic polyurethane 85A nanofiber membranes are transparent, and display superior filtration performance which meets up with the 95% filtration efficiency standard in GB 19083-2010 technical requirements for protective face mask for medical use. The lightweight pleated thermoplastic polyurethane/cellulose composites intercept ∼90% ultrafine PM0.3 under airflow velocity of 32 L min-1 and possess great resistance to shock. These hierarchically designed filters follow a mechanical mechanism and can be used in on-road and off-road cars in the long run.


Asunto(s)
Filtros de Aire , Celulosa , Filtración , Material Particulado , Poliuretanos
3.
J Environ Manage ; 342: 118142, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37182485

RESUMEN

In this study, a laboratory-scale vacuum membrane distillation (VMD) system coupled with microbubble aeration (MBA) was developed for the treatment of high-salinity brine containing organic matters. Herein, at the beginning, feedwater only containing model organics such as humic acid (HA), bovine serum albumin (BSA) and sodium alginate (SA) was utilized to investigate the organic-fouling behavior, results indicated that the permeate flux was not affected by a thin and loose contaminated layer deposited on the membrane surface. Furthermore, dissolved organics in the feed brine inhibited the occurrence of membrane wetting due to the existence of a compact and protective crystals/organic-fouling layer, which can prevent the intrusion of scaling ions into membrane substrates. Besides, organics in the feedwater have a high tendency to adsorb on the membrane surface based on molecular dynamics simulations, thus, forming an organic-fouling layer prior to inorganic scaling. Finally, the effect of MBA on fouling alleviation was evaluated in VMD system, nearly 50% of salt precipitation from fouled membrane was effectively removed with the introduction of MBA, which can be ascribed to a combination of mechanisms, including surface shear forces and electrostatic attractions induced by microbubbles, meanwhile, about 2.2% of the total energy was only consumed, when using MBA. Together, these results demonstrated that MBA was a promising approach to alleviate membrane fouling in VMD.


Asunto(s)
Microburbujas , Purificación del Agua , Materia Orgánica Disuelta , Destilación/métodos , Vacio , Salinidad , Membranas Artificiales , Purificación del Agua/métodos
4.
J Environ Manage ; 348: 119171, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37832287

RESUMEN

Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca2+), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation.


Asunto(s)
Sustancias Húmicas , Purificación del Agua , Sustancias Húmicas/análisis , Destilación/métodos , Microburbujas , Membranas Artificiales , Purificación del Agua/métodos , Cationes
5.
J Nanobiotechnology ; 20(1): 213, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35524280

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with pathophysiological characteristics of transforming growth factor-ß (TGF-ß), and reactive oxygen species (ROS)-induced excessive fibroblast-to-myofibroblast transition and extracellular matrix deposition. Macrophages are closely involved in the development of fibrosis. Nuclear factor erythroid 2 related factor 2 (Nrf2) is a key molecule regulating ROS and TGF-ß expression. Therefore, Nrf2 signaling modulation might be a promising therapy for fibrosis. The inhalation-based drug delivery can reduce systemic side effects and improve therapeutic effects, and is currently receiving increasing attention, but direct inhaled drugs are easily cleared and difficult to exert their efficacy. Therefore, we aimed to design a ROS-responsive liposome for the Nrf2 agonist dimethyl fumarate (DMF) delivery in the fibrotic lung. Moreover, we explored its therapeutic effect on pulmonary fibrosis and macrophage activation. RESULTS: We synthesized DMF-loaded ROS-responsive DSPE-TK-PEG@DMF liposomes (DTP@DMF NPs). DTP@DMF NPs had suitable size and negative zeta potential and excellent capability to rapidly release DMF in a high-ROS environment. We found that macrophage accumulation and polarization were closely related to fibrosis development, while DTP@DMF NPs could attenuate macrophage activity and fibrosis in mice. RAW264.7 and NIH-3T3 cells coculture revealed that DTP@DMF NPs could promote Nrf2 and downstream heme oxygenase-1 (HO-1) expression and suppress TGF-ß and ROS production in macrophages, thereby reducing fibroblast-to-myofibroblast transition and collagen production by NIH-3T3 cells. In vivo experiments confirmed the above findings. Compared with direct DMF instillation, DTP@DMF NPs treatment presented enhanced antifibrotic effect. DTP@DMF NPs also had a prolonged residence time in the lung as well as excellent biocompatibility. CONCLUSIONS: DTP@DMF NPs can reduce macrophage-mediated fibroblast-to-myofibroblast transition and extracellular matrix deposition to attenuate lung fibrosis by upregulating Nrf2 signaling. This ROS-responsive liposome is clinically promising as an ideal delivery system for inhaled drug delivery.


Asunto(s)
Fibrosis Pulmonar Idiopática , Factor 2 Relacionado con NF-E2 , Animales , Fibrosis , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Liposomas , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología
6.
Int Endod J ; 55(8): 882-888, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35543607

RESUMEN

AIM: To describe a novel surgical method (crown rotation surgery) to manage inversely impacted central incisors with immature roots. METHODOLOGY: Two young patients each presented with an inversely impacted maxillary central incisor. To protect the apical tissues, the two impacted incisors were rotated downwards to a relatively normal position without extraction from their bony sockets. RESULTS: After crown rotation surgery, spontaneous eruption, continuous root development, and periodontal healing of the rotated incisors were observed. The pulp retained vitality and blood flow was normal. Moreover, there were no obvious signs of pulp canal obliteration (PCO), as indicated by Cone Beam Computed Tomography (CBCT) imaging. CONCLUSIONS: By optimising protection of the vital pulp and apical tissues, crown rotation surgery represents a minimally invasive, conservative, and practical surgical technique for treating inversely impacted incisors with developing roots. In contrast to existing surgical methods, crown rotation surgery may avoid certain complications, including PCO and abnormal or arrested root development. KEY LEARNING POINTS: By optimizing protection of the vital pulp and apical tissues, crown rotation surgery represents a minimally invasive, conservative and practical surgical technique for treating inversely impacted incisors with developing roots. In contrast to existing surgical methods, crown rotation surgery may avoid certain complications, including PCO and abnormal or arrested root development.


Asunto(s)
Incisivo , Diente Impactado , Tomografía Computarizada de Haz Cónico/métodos , Coronas , Estudios de Seguimiento , Humanos , Incisivo/cirugía , Maxilar , Ápice del Diente , Raíz del Diente/diagnóstico por imagen , Raíz del Diente/cirugía , Diente Impactado/diagnóstico por imagen , Diente Impactado/cirugía
7.
J Nanobiotechnology ; 19(1): 440, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34930284

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) is a promising therapeutic modality that can convert oxygen into cytotoxic reactive oxygen species (ROS) via photosensitizers to halt tumor growth. However, hypoxia and the unsatisfactory accumulation of photosensitizers in tumors severely diminish the therapeutic effect of PDT. In this study, a multistage nanoplatform is demonstrated to overcome these limitations by encapsulating photosensitizer IR780 and oxygen regulator 3-bromopyruvate (3BP) in poly (lactic-co-glycolic acid) (PLGA) nanocarriers. RESULTS: The as-synthesized nanoplatforms penetrated deeply into the interior region of tumors and preferentially remained in mitochondria due to the intrinsic characteristics of IR780. Meanwhile, 3BP could efficiently suppress oxygen consumption of tumor cells by inhibiting mitochondrial respiratory chain to further improve the generation of ROS. Furthermore, 3BP could abolish the excessive glycolytic capacity of tumor cells and lead to the collapse of ATP production, rendering tumor cells more susceptible to PDT. Successful tumor inhibition in animal models confirmed the therapeutic precision and efficiency. In addition, these nanoplatforms could act as fluorescence (FL) and photoacoustic (PA) imaging contrast agents, effectuating imaging-guided cancer treatment. CONCLUSIONS: This study provides an ideal strategy for cancer therapy by concurrent oxygen consumption reduction, oxygen-augmented PDT, energy supply reduction, mitochondria-targeted/deep-penetrated nanoplatforms and PA/FL dual-modal imaging guidance/monitoring. It is expected that such strategy will provide a promising alternative to maximize the performance of PDT in preclinical/clinical cancer treatment.


Asunto(s)
Mitocondrias/efectos de los fármacos , Nanopartículas/química , Fármacos Fotosensibilizantes/farmacología , Hipoxia Tumoral/efectos de los fármacos , Animales , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Humanos , Indoles/química , Indoles/farmacocinética , Indoles/farmacología , Indoles/uso terapéutico , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Desnudos , Mitocondrias/metabolismo , Neoplasias/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacocinética , Fármacos Fotosensibilizantes/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Piruvatos/química , Piruvatos/farmacocinética , Piruvatos/farmacología , Piruvatos/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Distribución Tisular , Trasplante Heterólogo
8.
Am J Orthod Dentofacial Orthop ; 159(4): 536-544, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33568277

RESUMEN

Treatment of an impacted incisor with a dilacerated root is challenging for clinicians because of the position of the impacted incisor, the abnormality of the root, unfavorable prognosis, and, especially, the long treatment duration. We report on 2 young patients who had inversely impacted maxillary central incisors with developing labially dilacerated roots. Both patients were treated by a novel surgical approach, in situ rotation, by which the crowns of the inversely impacted incisors were carefully rotated to a relatively normal position, whereas the apical location remained relatively unchanged. About 2 weeks after surgery, spontaneous eruption of the treated incisors was observed. Three months later, the postoperative central incisors were further aligned into the maxillary arch with a fixed orthodontic appliance. Follow-up visits 2 or 3 years after surgery indicated that the positions of the dilacerated incisors maintained stability with good gingival esthetics, and the pulpal vitality was favorable. The roots grew further in a relatively normal direction of the incisor's longitudinal axis, which was different from the initial curvature angle. Moreover, with the in situ rotation surgery, treatment time was greatly reduced and resulted in a favorable prognosis compared with conventional treatment.


Asunto(s)
Incisivo , Diente Impactado , Estética Dental , Humanos , Incisivo/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Rotación , Raíz del Diente/diagnóstico por imagen , Raíz del Diente/cirugía , Diente Impactado/diagnóstico por imagen , Diente Impactado/cirugía
9.
Mol Pharm ; 17(5): 1586-1595, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32186879

RESUMEN

It is a challenging task to suppress the bitterness of liquid preparations, especially for children. Bitter molecules are highly dispersible in liquids, leading to a strong and instant stimulation of the bitter receptors. At present, there is no effective way to correct this issue except for adding sweeteners, resulting in an unsatisfying taste. Based on the three-point contact theory, which is a universally accepted mechanism of bitterness formation, a new idea and application of amphiphilic block copolymers (ABCs) for bitterness suppression was proposed for the first time. We found that ABCs could widely inhibit the bitterness of four typical bitter substances. The mechanism is that ABCs self-assemble to form association colloids, which attract bitter components and reduce their distribution in the molecular form in solution. The bitter components were demonstrated to automatically embed in the spiral hydrophobic cavity of the hydrophobic chain of the ABCs, and their special interaction dispersed the positive electrostatic potential of bitter groups. The combination did not affect the pharmacokinetic parameters and pharmacodynamics of bitter drugs. These findings highlight the novel application of ABCs for the inhibition of bitterness and illuminate the underlying inhibition mechanisms.


Asunto(s)
Polímeros/farmacología , Gusto/efectos de los fármacos , Animales , Berberina/farmacología , Masculino , Ratones , Micelas , Simulación del Acoplamiento Molecular , Poliésteres/farmacología , Polietilenglicoles/farmacología , Soluciones
10.
Biomacromolecules ; 21(12): 5345-5357, 2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-33307698

RESUMEN

Efficient therapeuic proteins' delivery into mammalian cells and subcellular transport (e.g., fast escape from endolysosomes into cytoplasm) are two key biological barriers that need to be overcome for antigen-based immunotherapy and related biomedical applications. For those purposes, we designed a novel kind of photoresponsive polypeptide-glycosylated poly(amidoamine) (PAMAM) dendron amphiphiles (PGDAs), and their synthesis, UV-responsive self-assembly, and triggered ovalbumin (OVA) release have been fully investigated. The highly anisotropic PGDA4 with a glycosylated second-generation PAMAM dendron self-assembled into stable polypeptide vesicles (polymersomes) within 20-50 wt % water, which exhibited UV-responsive reassembly, dynamic binding with a lectin of concanavalin A, and an accelerated OVA release in vitro. Moreover, upon 365 nm UV irradiation, the self-assembled polymersomes of those glycopolypeptides were transformed into micellar aggregates in aqueous solution at pH 7.4 but disassembled completely at pH 5. The OVA-loaded polymersomes could efficiently deliver OVA into RAW264.7 cells and achieve enhanced endolysosomes escape upon UV irradiation, as revealed by flow cytometry and confocal laser scanning microscopy (CLSM). Furthermore, the enzyme-linked immunosorbent assay (ELISA) showed that the blank sugar-coated polypeptidosomes activated a high level of tumor necrosis factor α (TNF-α) of 468 pg/mL, playing a better role of immune adjuvant for activating the macrophages. Upon the UV irradiation with a dose of 3 J/cm2, the OVA-loaded polymersomes could further stimulate RAW264.7 and enhance the TNF-α level by about 45%. Consequently, this work provides a versatile platform to construct photosensitive and sugar-coated polymersomes of glycopolypeptides that have potential applications for protein delivery, immune adjuvant, and antigen-based immunotherapy.


Asunto(s)
Dendrímeros , Animales , Inmunidad , Micelas , Ovalbúmina , Polietilenglicoles
11.
Anal Bioanal Chem ; 412(12): 2863-2871, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32112131

RESUMEN

Cyanide (C≡N) can lead to blood, cardiovascular system, and nervous system disorders owing to the acute and chronic toxicity; thus, aiming at the group or individual poisoning incidents, it is necessary to develop the sensitive and credible method for rapid on-site detection of poisons cyanide. Surface-enhanced Raman spectroscopy (SERS) with the advantages of providing fingerprint information of target molecules and single-molecules sensitivity has been widely used in on-site analysis; however, the SERS measurements always suffer from the problem of the stability of substrates. Here, the polyvinylpyrrolidone (PVP)-stabilized Au NPs (PVP-Au NPs) have been assembled through the simple, convenient evaporation-induced strategy with the large-scale hotspots substrates. The presence of PVP can not only facilitate the assembly of Au NPs but also prevent the corrosion of CN- towards the Au NPs with the formation of [Au (CN)2]-1, providing high stable and reproducible SERS signals. Moreover, the PVP-Au NPs have been assembled on the Si wafer to fabricate the portable SERS chip for rapid on-site detection of CN- with an RSD of 5.8% and limitation of 100 ppb. Furthermore, by coupling a portable Raman spectrometer, the SERS spectra of CN- spiked into different specimens to simulate the poison samples have been collected and analyzed on SERS chips with the recovery of 89-103% and RSD not higher than 11.3%. Consequently, the fabricated SERS chip with assembled PVP-Au NPs can provide sensitive and credible detection for CN- in different specimens, and then would satisfy the rapid on-site evaluation of CN- in poisoning incidents with the portable Raman spectrometer. Graphical Abstract.


Asunto(s)
Cianuros/análisis , Oro/química , Nanopartículas del Metal/química , Povidona/química , Espectrometría Raman/métodos , Contaminantes Químicos del Agua/análisis , Propiedades de Superficie
12.
Pediatr Cardiol ; 41(4): 716-723, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32006083

RESUMEN

Transcatheter closure of large atrial septal defects (ASDs) remains controversial. The aim of this study was to evaluate the feasibility and safety of transthoracic echocardiography (TTE)-guided transcatheter closure of large ASDs. Patients with large secundum ASDs (≥ 30 mm) who underwent device closure were retrospectively reviewed. TTE was performed to guide ASD occluder positioning and assess the immediate and long-term outcomes. A total of 60 patients (median age 43.5 years, range 15-78 years) were enrolled in the study. The median ASD size was 35 mm (range 30-42 mm). Mild to moderate pulmonary hypertension was observed in 36 patients (60%). Thirty-one patients (51.7%) had one short rim, and 18 patients (30.0%) had two deficient rims. Placement of the device was successful in 57 patients (95%), and the median device size was 42 mm (range 40-50 mm). Dislodgement of the device occurred in three patients with two deficient rims: a larger device was redeployed in one case, and two patients required surgical repair. During a median follow-up of 37 months (range 6-83 months), no residual shunts, erosion, or embolization were noted, and pulmonary hypertension resolved in 75% of the patients. Thus t vast majority (95%) of large ASDs can be successfully closed percutaneously using the Chinese-made Shanghai Shape Memory Alloy (SHSMA) occluder under TTE guidance. Long-term follow-up showed that transcatheter closure could become a safe and effective alternative to surgery in select large ASDs.


Asunto(s)
Ecocardiografía/instrumentación , Defectos del Tabique Interatrial/terapia , Dispositivo Oclusor Septal , Adolescente , Adulto , Anciano , Niño , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Defectos del Tabique Interatrial/patología , Humanos , Hipertensión Pulmonar/terapia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Aleaciones con Memoria de Forma/uso terapéutico , Adulto Joven
13.
Plant Cell Physiol ; 60(4): 788-801, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30590744

RESUMEN

Plant mechanical strength contributes to lodging resistance and grain yield, making it an agronomically important trait in sorghum (Sorghum bicolor). In this study, we isolated the brittle culm 1 (bc1) mutant and identified SbBC1 through map-based cloning. SbBC1, a homolog of rice OsBC1 and Arabidopsis thaliana AtCOBL4, encodes a COBRA-like protein that exhibits typical structural features of a glycosylphosphatidylinositol-anchored protein. A single-nucleotide mutation in SbBC1 led to reduced mechanical strength, decreased cellulose content, and increased lignin content without obviously altering plant morphology. Transmission electron microscopy revealed reduced cell wall thickness in sclerenchyma cells of the bc1 mutant. SbBC1 is primarily expressed in developing sclerenchyma cells and vascular bundles in sorghum. RNA-seq analysis further suggested a possible mechanism by which SbBC1 mediates cellulose biosynthesis and cell wall remodeling. Our results demonstrate that SbBC1 participates in the biosynthesis of cellulose in the secondary cell wall and affects the mechanical strength of sorghum plants, providing additional genetic evidence for the roles of COBRA-like genes in cellulose biosynthesis in grasses.


Asunto(s)
Pared Celular/metabolismo , Celulosa/metabolismo , Sorghum/metabolismo , Autoinmunidad/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas Quinasas Activadas por Mitógenos/metabolismo
14.
Environ Microbiol ; 19(3): 1054-1064, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27878934

RESUMEN

The recalcitrance of lignocellulose forms a strong barrier for the bioconversion of lignocellulosic biomass in chemical or biofuel industries. Filamentous fungi are major plant biomass decomposer, and capable of forming all the required enzymes. Here, they characterized the GH10 and GH11 endo-xylanases and a CE1 acetyl-xylan esterase (Axe1) from a superior biomass-degrading strain, Aspergillus fumigatus Z5, and examined how they interact in xylan degradation. Cellulose-binding (CBM1) domain inhibited GH10 xylanase activities for pure xylan, but afforded them an ability to hydrolyze washed corncob particles (WCCP). CBM1-containing GH10 xylanases also showed synergism with CBM1-containing Axe1 in WCCP hydrolysis, and this synergy was strictly dependent on the presence of their CBM1 domains. In contrast, GH11 xylanases had no CBM1, but still could bind xylan and hydrolyzed WCCP; however, no synergism displayed with Axe1. GH10 xylanases and GH11 xylanases showed a pronounced synergism in WCCP hydrolysis, which was dependent on the presence of the CBM1 in GH10 xylanases and absence from GH11 xylanases. They exhibit different mechanisms to bind to cellulose and xylan, and act in synergy when these two structures are intact. These findings will be helpful for the further development of highly efficient enzyme mixtures for lignocellulosic biomass conversion.


Asunto(s)
Endo-1,4-beta Xilanasas/metabolismo , Hongos/metabolismo , Lignina/metabolismo , Polisacáridos/metabolismo , Xilanos/metabolismo , Biomasa , Celulosa/metabolismo , Hidrólisis
15.
Zhongguo Zhong Yao Za Zhi ; 42(1): 113-118, 2017 Jan.
Artículo en Zh | MEDLINE | ID: mdl-28945034

RESUMEN

To prepare the intrauterine slow release silicone rubber bar made of Panax notoginseng and Rubia cordifolia, and finish its preliminary evaluation of in vitro releasing properties. The open mill method was used for plasticating of silicone rubber. The process parameters of the silicone rubber and drugs mixing were optimized by orthogonal test. The parameters of silicone rubber vulcanization was optimized by single factor test. The preliminary evaluation of in vitro release performance of the silicone rubber bar was conducted with ginsenoside Rg1, ginsenoside Rb1, notoginsenoside R1, purpurin and rubimaillin as the indexes. The results showed that optimum technologic parameters for silicone rubber and drugs mixing:the roller spacing 2 mm; speed ratio 1∶1.2; front roller temperature 55-60 ℃; rear roll temperature 50-55 ℃; and mixing time 20 min. The optimum parameters for silicone rubber vulcanization:temperature 90 ℃, and time 60 min. The studies on release process in vitro revealed that the release process of silicone rubber bar was in line with the Higuchi equations. After 90 days, the cumulative release of ginsenoside Rg1, ginsenoside Rb1 and notoginsenoside R1 was 46.7%, and the cumulative release of purpurin and rubimaillin was 51.9%. The preparation method can be applied to the preparation of silicone rubber bar, with slow release characteristics.


Asunto(s)
Liberación de Fármacos , Medicamentos Herbarios Chinos/química , Ginsenósidos/química , Panax notoginseng/química , Rubia/química , Elastómeros de Silicona/química
16.
BMC Genomics ; 16: 459, 2015 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-26076650

RESUMEN

BACKGROUND: Various saprotrophic microorganisms, especially filamentous fungi, can efficiently degrade lignocellulose that is one of the most abundant natural materials on earth. It consists of complex carbohydrates and aromatic polymers found in the plant cell wall and thus in plant debris. Aspergillus fumigatus Z5 was isolated from compost heaps and showed highly efficient plant biomass-degradation capability. RESULTS: The 29-million base-pair genome of Z5 was sequenced and 9540 protein-coding genes were predicted and annotated. Genome analysis revealed an impressive array of genes encoding cellulases, hemicellulases and pectinases involved in lignocellulosic biomass degradation. Transcriptional responses of A. fumigatus Z5 induced by sucrose, oat spelt xylan, Avicel PH-101 and rice straw were compared. There were 444, 1711 and 1386 significantly differently expressed genes in xylan, cellulose and rice straw, respectively, when compared to sucrose as a control condition. CONCLUSIONS: Combined analysis of the genomic and transcriptomic data provides a comprehensive understanding of the responding mechanisms to the most abundant natural polysaccharides in A. fumigatus. This study provides a basis for further analysis of genes shown to be highly induced in the presence of polysaccharide substrates and also the information which could prove useful for biomass degradation and heterologous protein expression.


Asunto(s)
Aspergillus fumigatus/genética , Proteínas Fúngicas/genética , Lignina/genética , Transcriptoma/genética , Biomasa , Celulasas/genética , Celulosa/genética , Hongos/genética , Perfilación de la Expresión Génica/métodos , Genoma Fúngico/genética , Genómica/métodos , Glicósido Hidrolasas/genética , Transcripción Genética/genética
17.
Appl Environ Microbiol ; 81(15): 5144-56, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26002897

RESUMEN

Traditional Chinese solid-state fermented cereal starters contain highly complex microbial communities and enzymes. Very little is known, however, about the microbial dynamics related to environmental conditions, and cellulolytic communities have never been proposed to exist during cereal starter fermentation. In this study, we performed Illumina MiSeq sequencing combined with PCR-denaturing gradient gel electrophoresis to investigate microbiota, coupled with clone library construction to trace cellulolytic communities in both fermentation stages. A succession of microbial assemblages was observed during the fermentation of starters. Lactobacillales and Saccharomycetales dominated the initial stages, with a continuous decline in relative abundance. However, thermotolerant and drought-resistant Bacillales, Eurotiales, and Mucorales were considerably accelerated during the heating stages, and these organisms dominated until the end of fermentation. Enterobacteriales were consistently ubiquitous throughout the process. For the cellulolytic communities, only the genera Sanguibacter, Beutenbergia, Agrobacterium, and Erwinia dominated the initial fermentation stages. In contrast, stages at high incubation temperature induced the appearance and dominance of Bacillus, Aspergillus, and Mucor. The enzymatic dynamics of amylase and glucoamylase also showed a similar trend, with the activities clearly increased in the first 7 days and subsequently decreased until the end of fermentation. Furthermore, ß-glucosidase activity continuously and significantly increased during the fermentation process. Evidently, cellulolytic potential can adapt to environmental conditions by changes in the community structure during the fermentation of starters.


Asunto(s)
Bacterias/clasificación , Biota , Celulosa/metabolismo , Grano Comestible/metabolismo , Grano Comestible/microbiología , Hongos/clasificación , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , China , Electroforesis en Gel de Gradiente Desnaturalizante , Enzimas/análisis , Fermentación , Hongos/crecimiento & desarrollo , Hongos/metabolismo , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Temperatura , Factores de Tiempo
18.
BMC Cancer ; 14: 800, 2014 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-25367065

RESUMEN

BACKGROUND: Superparamagnetic poly (lactic-co-glycolic acid) (PLGA)-coated Fe3O4 microcapsules are receiving increased attention as potential diagnostic and therapeutic modalities in the field of oncology. In this study, PLGA-coated Fe3O4 microcapsules were combined with a magnetic resonance imaging-guided high-intensity focused ultrasound (MR-guided HIFU) platform, with the objective of investigating the effects of these composite microcapsules regarding MR-guided HIFU liver cancer surgery in vivo. METHODS: PLGA-coated Fe3O4 microcapsules consisting of a liquid core and a PLGA-Fe3O4 shell were fabricated using a modified double emulsion evaporation method. Their acute biosafety was confirmed in vitro using MDA cells and in vivo using rabbits. To perform MR-guided HIFU surgery, the microcapsules were intravenously injected into a rabbit liver tumor model before MR-guided HIFU. T2-weighted images and MR signal intensity in normal liver parenchyma and tumor tissue were acquired before and after injection, to assess the MR imaging ability of the microcapsules. After MR-guided HIFU ablation tissue temperature mapping, the coagulative volume and histopathology of the tumor tissue were analyzed to investigate the ablation effects of MR-guided HIFUs. RESULTS: Scanning and transmission electron microscopy showed that the microcapsules displayed a spherical morphology and a shell-core structure (mean diameter, 587 nm). The hysteresis curve displayed the typical superparamagnetic properties of the microcapsules, which are critical to their application in MR-guided HIFU surgery. In MR-guided HIFU surgery, these microcapsules functioned as an MRI contrast agent, induced significant hyperthermal enhancement (P < 0.05) and significantly enhanced the volume of coagulative necrosis (P < 0.05). CONCLUSIONS: The administration of PLGA-coated Fe3O4 microcapsules is a potentially synergistic technique regarding the enhancement of MR-guided HIFU cancer surgery.


Asunto(s)
Cápsulas/química , Cápsulas/uso terapéutico , Óxido Ferrosoférrico/química , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Neoplasias Hepáticas/terapia , Polímeros/química , Animales , Cápsulas/administración & dosificación , Modelos Animales de Enfermedad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/ultraestructura , Conejos , Factores de Tiempo
19.
Nanoscale ; 16(25): 12149-12162, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38833269

RESUMEN

Together, tumor and virus-specific tissue-resident CD8+ memory T cells (TRMs) of hepatocellular carcinoma (HCC) patients with Hepatitis B virus (HBV) infection can provide rapid frontline immune surveillance. The quantity and activity of CD8+ TRMs were correlated with the relapse-free survival of patients with improved health. However, HBV-specific CD8+ TRMs have a more exhausted phenotype and respond more actively under anti-PDL1 or PD1 treatment of HBV+HCC patients. Vaccination strategies that induce a strong and sustained CD8+ TRMs response are quite promising. Herein, a biodegradable poly(D,L-lactide-co-glycolide) microsphere and nanosphere particle (PLGA N.M.P) delivery system co-assembled by anti-PD1 antibodies (aPD1) and loaded with ovalbumin (OVA-aPD1 N.M.P) was fabricated and characterized for size (200 nm and 1 µm diameter), charge (-15 mV), and loading efficiencies of OVA (238 µg mg-1 particles) and aPD1 (40 µg mg-1 particles). OVA-aPD1 N.M.P could stimulate the maturation of BMDCs and enhance the antigen uptake and presentation by 2-fold compared to free OVA. The nanoparticles also induced the activation of macrophages (RAW 264.7) to produce a high level of cytokines, including TNF-α, IL-6 and IL-10. In vivo stimulation of mice using OVA-aPD1 N.M.P robustly enhanced IFN-γ-producing-CD8+ T cell infiltration in tumor tissues and the secretion of IgG and IgG2a/IgG1 antibodies. OVA-aPD1 N.M.P delivered OVA to increase the activation and proliferation of OVA-specific CD8+ TRMs, and its combination with anti-PD1 antibodies promoted complete tumor rejection by the reversal of tumor-infiltrating CD8+ T cell exhaustion. Thus, PLGA N.M.P could induce a strong CD8+ TRMs response, further highlighting its therapeutic potential in enhancing an antitumor immune response.


Asunto(s)
Linfocitos T CD8-positivos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Ratones , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Ratones Endogámicos C57BL , Ovalbúmina/inmunología , Ovalbúmina/química , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Nanopartículas/química , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/química , Células T de Memoria/inmunología , Vacunación , Humanos , Células RAW 264.7 , Memoria Inmunológica
20.
Nanotechnology ; 24(29): 295101, 2013 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-23799649

RESUMEN

To construct mannosylated liposomes/protamine/DNA (LPD) carriers for DNA vaccine targeting to dendritic cells (DCs), a mannosylated cholesterol derivative (Man-C6-Chol) was synthesized via simple ester linkage and amide bonds. Then, the Man-C6-Chol was applied to LPD formulation as a synthetic ligand. The physicochemical properties of mannosylated LPD (Man-LPD) were first evaluated, including the size and zeta potential, morphology and the ability to protect DNA against DNase I degradation. Man-LPD showed a small size with a stable viral-like structure. In comparison to non-mannose liposomes/LPD (Man-free liposomes/LPD), mannosylated liposomes/LPD (Man-liposomes/Man-LPD) exhibited higher efficiency in both intracellular uptake (2.3-fold) and transfection (4.5-fold) in vitro. Subsequent MTT assays indicated that the LPD carriers had low toxicity on the tested cells. Afterwards, the investigation into the maturation activation on primary bone marrow-derived DCs (BMDCs) showed that both Man-LPD and Man-free LPD induced remarkable up-regulation of CD80, CD86 and CD40 on BMDCs. Inspired by these studies, we can conclude that the synthetic mannosylated LPD targeting to DCs was a potential carrier for DNA vaccine.


Asunto(s)
Colesterol/análogos & derivados , Células Dendríticas/metabolismo , Liposomas/metabolismo , Vacunas de ADN/administración & dosificación , Animales , Línea Celular , Células Cultivadas , Colesterol/metabolismo , Humanos , Liposomas/química , Masculino , Manosa/análogos & derivados , Manosa/metabolismo , Ratones , Ratones Endogámicos C57BL , Protaminas/química , Protaminas/metabolismo , Transfección , Vacunas de ADN/genética
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