Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 101
Filtrar
1.
J Nanobiotechnology ; 22(1): 322, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849858

RESUMO

The ideal tissue engineering scaffold should facilitate rapid cell infiltration and provide an optimal immune microenvironment during interactions with the host. Electrospinning can produce two-dimensional (2D) membranes mimicking the extracellular matrix. However, their dense structure hinders cell penetration, and their thin form restricts scaffold utility. In this study, latticed hydrogels were three-dimensional (3D) printed onto electrospun membranes. This technique allowed for layer-by-layer assembly of the membranes into 3D scaffolds, which maintained their resilience impressively under both dry and wet conditions. We assessed the cellular and host responses of these 3D nanofiber scaffolds by comparing random membranes and mesh-like membranes with three different mesh sizes (250, 500, and 750 µm). It was found that scaffolds with a mesh size of 500 µm were superior for M2 macrophage phenotype polarization, vascularization, and matrix deposition. Furthermore, it was confirmed by subsequent experiments such as RNA sequencing that the mesh-like topology may promote polarization to the M2 phenotype by affecting the PI3K/AKT pathway. In conclusion, our work offers a novel method for transforming 2D nanofiber membranes into 3D scaffolds. This method boasts flexibility, allowing for the use of varied electrospun membranes and hydrogels in terms of structure and composition. It has vast potential in tissue repair and regeneration.


Assuntos
Hidrogéis , Nanofibras , Impressão Tridimensional , Medicina Regenerativa , Engenharia Tecidual , Alicerces Teciduais , Nanofibras/química , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Medicina Regenerativa/métodos , Hidrogéis/química , Animais , Camundongos , Macrófagos/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Células RAW 264.7 , Humanos
2.
J Nanobiotechnology ; 22(1): 153, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580995

RESUMO

BACKGROUND: Osteoporosis is characterized by an imbalance in bone homeostasis, resulting in the excessive dissolution of bone minerals due to the acidified microenvironment mediated by overactive osteoclasts. Oroxylin A (ORO), a natural flavonoid, has shown potential in reversing osteoporosis by inhibiting osteoclast-mediated bone resorption. The limited water solubility and lack of targeting specificity hinder the effective accumulation of Oroxylin A within the pathological environment of osteoporosis. RESULTS: Osteoclasts' microenvironment-responsive nanoparticles are prepared by incorporating Oroxylin A with amorphous calcium carbonate (ACC) and coated with glutamic acid hexapeptide-modified phospholipids, aiming at reinforcing the drug delivery efficiency as well as therapeutic effect. The obtained smart nanoparticles, coined as OAPLG, could instantly neutralize acid and release Oroxylin A in the extracellular microenvironment of osteoclasts. The combination of Oroxylin A and ACC synergistically inhibits osteoclast formation and activity, leading to a significant reversal of systemic bone loss in the ovariectomized mice model. CONCLUSION: The work highlights an intelligent nanoplatform based on ACC for spatiotemporally controlled release of lipophilic drugs, and illustrates prominent therapeutic promise against osteoporosis.


Assuntos
Reabsorção Óssea , Osteoporose , Camundongos , Animais , Osteoclastos , Nanomedicina , Osteoporose/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Osso e Ossos/patologia , Diferenciação Celular
3.
Xenotransplantation ; 30(1): e12787, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36454040

RESUMO

OBJECTIVE: Islet allotransplantation has demonstrated improved clinical outcomes using the hepatic portal vein as the standard infusion method. However, the current implantation site is not ideal due to the short-term thrombotic and long-term immune destruction. Meanwhile, the shortage of human organ donors further limits its application. To find a new strategy, we tested a new polymer combination for islet encapsulation and transplantation. Meanwhile, we explored a new site for xenogeneic islet transplantation in mice. METHOD: We synthesized a hydrogel combining alginate plus poly-ethylene-imine (Alg/PEI) for the encapsulation of rat, neonatal porcine, and human islets. Transplantation was performed into the retroperitoneal retro-colic space of diabetic mice. Control mice received free islets under the kidney capsule or encapsulated islets into the peritoneum. The biochemical indexes were measured, and the transplanted islets were harvested for immunohistochemical staining of insulin and glucagon. RESULTS: Mice receiving encapsulated rat, porcine and human islets transplanted into the retroperitoneal space maintained normoglycemia for a median of 275, 145.5, and 146 days, respectively. In contrast, encapsulated xenogeneic islets transplanted into the peritoneum, maintained function for a median of 61, 95.5, and 82 days, respectively. Meanwhile, xenogeneic islets transplanted free into the kidney capsule lost their function within 3 days after transplantation. Immunohistochemical staining of encapsulated rat, porcine and human islets, retrieved from the retroperitoneal space, allowed to distinguish morphological normal insulin expressing ß- and glucagon expressing α-cells at 70, 60, and 100 days post-transplant, respectively. CONCLUSION: Transplantation of Alg/PEI encapsulated xenogeneic islets into the retroperitoneal space provides a valuable new implantation strategy for the treatment of type 1 diabetes.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Ratos , Camundongos , Suínos , Humanos , Animais , Ilhotas Pancreáticas/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Transplante Heterólogo/métodos , Diabetes Mellitus Experimental/cirurgia , Espaço Retroperitoneal , Glucagon , Insulina
4.
Small ; 18(43): e2107048, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35229459

RESUMO

Single-crystalline cathodes are the most promising candidates for high-energy-density lithium-ion batteries (LIBs). Compared to their polycrystalline counterparts, single-crystalline cathodes have advantages over liquid-electrolyte-based LIBs in terms of cycle life, structural stability, thermal stability, safety, and storage but also have a potential application in solid-state LIBs. In this review, the development history and recent progress of single-crystalline cathodes are reviewed, focusing on properties, synthesis, challenges, solutions, and characterization. Synthesis of single-crystalline cathodes usually involves preparing precursors and subsequent calcination, which are summarized in the details. In the following sections, the development issues of single-crystalline cathodes, including kinetic limitations, interfacial side reactions, safety issues, reversible planar gliding and micro-cracking, and particle size distribution and agglomeration, are systematically analyzed, followed by current solutions and characterization techniques. Finally, this review is concluded with proposed research thrusts for the future development of single-crystalline cathodes.

5.
Plant Biotechnol J ; 20(11): 2159-2173, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35869670

RESUMO

Microbiota colonize every accessible plant tissue and play fundamental roles in plant growth and health. Soybean stay-green syndrome (SGS), a condition that causes delayed leaf senescence (stay-green), flat pods and abnormal seeds of soybean, has become the most serious disease of soybean in China. However, the direct cause of SGS is highly debated, and little is known about how SGS affect soybean microbiome dynamics, particularly the seed microbiome. We studied the bacterial, fungal, and viral communities associated with different soybean tissues with and without SGS using a multi-omics approach, and investigated the possible pathogenic agents associated with SGS and how SGS affects the assembly and functions of plant-associated microbiomes. We obtained a comprehensive view of the composition, function, loads, diversity, and dynamics of soybean microbiomes in the rhizosphere, root, stem, leaf, pod, and seed compartments, and discovered that soybean SGS was associated with dramatically increased microbial loads and dysbiosis of the bacterial microbiota in seeds. Furthermore, we identified a novel geminivirus that was strongly associated with soybean SGS, regardless of plant cultivar, sampling location, or harvest year. This whole-plant microbiome profiling of soybean provides the first demonstration of geminivirus infection associated with microbiota dysbiosis, which might represent a general microbiological symptom of plant diseases.


Assuntos
Geminiviridae , Microbiota , Glycine max/genética , Glycine max/microbiologia , Disbiose , Microbiota/genética , Rizosfera , Bactérias , Raízes de Plantas/microbiologia
6.
Macromol Rapid Commun ; 43(14): e2100845, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35032147

RESUMO

Generally, nanostructured polymer particles are prepared by 3D confined self-assembly (3D-CSA) of block copolymers (BCPs), while micelles are obtained through self-assembly of BCPs in dilute solutions. Herein, a facile yet robust strategy is developed to regulate the assembled structures of BCP, poly(styrene-block-4-vinylpyridine) (PS-b-P4VP), from nanostructured particles to micelles. The assemblies are prepared by an emulsion-solvent diffusion-induced self-assembly route, which is conducted by dialysis. A key feature of this strategy is that a P4VP-selective solvent (e.g., ethanol) is added to the dialysate to tune the interfacial behavior of the droplets and assembled structures of PS-b-P4VP. The authors' results reveal that in the presence of slight ethanol, the surface and internal structural transitions of nanostructured particles are caused by changes in the interfacial selectivity and packing parameter. Interestingly, interfacial instability, which results in the formation of micelles, is observed when the dialysate contains 50 vol% ethanol or more. The reason can be ascribed to the decreased interface tension, which is induced by the increase in ethanol and enhanced solubility of P4VP. This facile strategy provides a new opportunity to bridge the gap between traditional 3D-CSA and solution self-assembly of BCPs, offering a promising route to engineer morphologies and nanostructures of polymeric assemblies.


Assuntos
Micelas , Polímeros , Soluções para Diálise , Emulsões , Etanol , Polímeros/química , Solventes/química
7.
Small ; 17(18): e2007570, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33734588

RESUMO

Halogen-bond driven assembly, a world parallel to hydrogen-bond, has emerged as an attractive tool for constructing (macro)molecular arrangement. However, knowledge about halogen-bond mediated confined-assembly in emulsion droplets is limited so far. An I…. N bond mediated confined-assembly pathway to enable order-order phase transitions is reported here. Compared to hydrogen bonds, the distinct features of halogen bonds (e.g., higher directionality, hydrophobicity, favored in polar solvents), offers opportunities to achieve novel nanostructures and materials. Polystyrene-b-poly(4-vinyl pyridine) (PS-b-P4VP) AB diblock copolymer is chosen as halogen acceptor, while an iodotetrafluorophenoxy substituted C-type homopolymer, (poly(3-(2,3,5,6-tetrafluoro-4-iodophenoxy)propyl acrylate), PTFIPA) is designed as halogen donor, synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Formation of halogen bonding donor-acceptor pairs between the PTFIPA homopolymer and the P4VP segments presented in PS-b-P4VP, increase the volume of P4VP domains, in turn inducing an order-to-order morphology transition sequence: changing from spherical → cylindrical → lamellar → inverse cylindrical, by tuning the PTFIPA content and choice of surfactant. Subsequent selective swelling/deswelling of the P4VP domains give rise to further internal morphology transitions, creating tailored mesoporous microparticles, disassembled nanodiscs, and superaggregates. It is believed that these results will stimulate further examinations of halogen bonding interactions in emulsion droplets and many areas of application.

8.
J Biochem Mol Toxicol ; 35(5): e22723, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33511709

RESUMO

Gastric carcinoma is one of the most aggressive types of cancer that ranks fifth among all cancer incidences and third in cancer mortality. As it exhibits a prolonged asymptomatic condition and high recurrence rate, it is a great challenge to treat gastric cancer. Traditional medicine that utilizes herbal phytochemicals to treat various diseases is a potent alternative for current allopathic treatment. Hence, we evaluated the potency of a phytochemical bilobalide for treating gastric cancer in in vitro and in vivo models. Bilobalide, a sesquiterpenoid, is present in the Ginkgo biloba plant that belongs to the family of Ginkgoaceae. The cytotoxicity effect of bilobalide was evaluated in both gastric cancer (AGS) cells and normal gastric epithelial cells. Apoptosis-inducing property of bilobalide against the AGS cell line was analyzed with different fluorescent staining techniques and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, and cell cycle analysis was carried out by flow cytometry. The in vivo studies were assessed with N-methyl-N-nitrosourea (MNU)-induced gastric cancer in rats. Serum-specific gastric markers were quantified and histopathological analysis of stomach tissue was performed. The expression of target-signaling molecules was analyzed by a reverse-transcription polymerase chain reaction. The in vitro results proved that bilobalide effectively suppressed the AGS cell growth and induced cell death by nuclear damage and apoptosis induction. The bilobalide treatment effectively arrested the cell cycle of AGS cells via inhibiting the PI3K-signaling pathway. Our in vivo results also confirmed that the bilobalide persuasively inhibited the MNU-induced gastric carcinoma via inhibiting the thioredoxin-fold family proteins and inflammatory markers' expression. Overall, our results authentically prove that bilobalide possesses therapeutic potency to cure gastric carcinoma.


Assuntos
Apoptose/efeitos dos fármacos , Bilobalídeos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Experimentais/tratamento farmacológico , Extratos Vegetais/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Bilobalídeos/química , Linhagem Celular Tumoral , Ginkgo biloba , Humanos , Masculino , Metilnitrosoureia/toxicidade , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Ratos , Ratos Wistar , Neoplasias Gástricas/induzido quimicamente , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
9.
Nano Lett ; 20(10): 7716-7721, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32946240

RESUMO

Implant loosening is still the major form of the failure of artificial joints. Herein, inspired by the operculum of the river snail, we prepared a novel bionic micro/nanoscale topography on a titanium surface. This bionic topography promoted early cell adhesion through up-regulating the expression of ITG α5ß1 and thus accelerated the following cell spreading, proliferation, and differentiation. Moreover, a miR-21 coating, which promoted the angiogenic differentiation of MSCs, was fabricated on the bionic topography. Benefiting from both bionic micro/nanoscale topography and miR-21, blood vessel growth and bone formation and mineralization around the implant, as well as bone-implant bonding strength, were significantly improved. Collectively, the present study highlights the combination of the bionic micro/nanoscale topography and miR-21 on promoting cell adhesion and angiogenic differentiation and improving in vivo angiogenesis and bone-implant osseointegration. This work provides a new train of thought propelling the development of implants for potential application in the orthopedics field.


Assuntos
Biônica , MicroRNAs , Adesão Celular , Diferenciação Celular , Materiais Revestidos Biocompatíveis , MicroRNAs/genética , Osseointegração , Propriedades de Superfície , Titânio
10.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1345-1356, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787131

RESUMO

Myocardial ischemia-reperfusion injury(MIRI) is an urgent problem in clinical treatment. As cardiomyocytes are terminal cells, MIRI-induced cardiomyocyte death will irreversibly damage the structure and function of the heart. In previous studies, apoptosis was considered to be the only way to regulate cell death, while necrosis could not be regulated. However, current studies have shown that cell necrosis could also be regulated, which was collectively called programmed cell death(PCD). Regulated cell death is actively mediated through molecular pathways, so there is the possibility of inhibiting this signaling to reduce MIRI. At present, PCD mainly includes apoptosis, autophagy, necrosis, pyroptosis and ferroptosis. As a unique treature in China, traditional Chinese medicine has the advantages of multiple pathways, multiple targets, low toxicity, less side effects and low economic costs. With the in-depth study of the efficacy of traditional Chinese medicine against MIRI, it has been confirmed that traditional Chinese medicine could regulate PCD to reduce MIRI. Therefore, this paper focuses on the relationship between PCD and MIRI, and new studies on intervention with relevant traditional Chinese medicine, with the aim to provide new MIRI prevention and treatment methods from the perspective of "intervention of PCD".


Assuntos
Traumatismo por Reperfusão Miocárdica , Apoptose , China , Humanos , Medicina Tradicional Chinesa , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/genética , Miócitos Cardíacos
11.
Phys Chem Chem Phys ; 22(3): 1194-1203, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31848533

RESUMO

Hierarchical self-assembly offers an elegant and energy-efficient bottom-up strategy for the fabrication of complex materials with precisely controllable morphologies and internal structures. Herein, pupa-like multicompartment micelles (MCMs) were readily fabricated via the hierarchical self-assembly of a polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) and polystyrene-block-poly(N-isopropylacrylamide) (PS-b-PNIPAM) block copolymer mixture in a THF/water mixture solvent, which were unable to be obtained by any of the individual block copolymers (BCPs). This means that the hierarchical self-assembly is a result of the synergistic cooperation between the two BCPs. Moreover, a kinetic study revealed that the MCMs were formed by hierarchical self-assembly of small spherical micelles (SSMs), which were co-assembled from the PS-b-P4VP/PS-b-PNIPAM mixture. Subsequently, we investigated the self-assembly of a PS-b-P4VP/PS-b-PNIPAM mixed solution confined in the nanopores of an anodic aluminum oxide (AAO) template. In such two-dimensional confinement, long multicompartment micelles (LMCMs) with a period multilayer structure were obtained. Notably, the confinement effect of nanopores on the hierarchical self-assembly could be distinguished into two different situations according to the activity of secondary assembly of the preformed SSMs from different BCP compositions, i.e., dynamic and static confinement. The dynamic confinement can affect the Brownian movement of SSMs and thus promotes their fusion to form spherical micelles with larger size compared with the SSMs formed under an unconfined condition. For the situation where AAO nanopores were partially filled with the preformed SSMs, the static confinement could decrease the stretching of BCP chains along the short axis of LMCMs and thus induce the formation of long range ordered multilayer nanostructures. These results illustrated that the synergistic effect played an important role in the hierarchical assembly of BCPs; meanwhile, such hierarchical self-assembly could be further manipulated by cylindrical confinement to rationally tune the nanostructures and dimensions of the BCP assemblies.

12.
Langmuir ; 35(9): 3461-3469, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30734559

RESUMO

Anisotropic polymer particles have promising applications in various fields, whereas their preparation usually suffers from tedious procedures. Here, we introduce a facile strategy to fabricate novel shape-anisotropic particles with varied internal structures via self-assembly of block copolymers (BCPs), with perfluorooctane (PFO) as the liquid template in emulsion droplets. By increasing the volume ratio of PFO to polystyrene- block-poly(4-vinylpyridine) (PS- b-P4VP) or decreasing the initial concentration of the BCPs, the self-assembled polymer particles change from spherical core-shell structures to anisotropic particles. Moreover, the anisotropic shape and internal structure of the polymer particles, including cone-like particles with alternative PS and P4VP lamellas, crescent-shaped particles with cylindrical P4VP domains, and plate-like particles with spherical P4VP domains, can be obtained by changing the block ratio or molecular weight or by adding a hydrogen-bonding agent. Based on the in situ optical microscopy investigation of the morphology evolution of the emulsion droplet, we conclude that both kinetic and thermodynamic factors during emulsion evolution determine the formation of shape-anisotropic polymeric particles with controllable internal structures.

13.
Langmuir ; 35(1): 141-149, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30507203

RESUMO

Kinetically controlled self-assembly of block copolymers (BCPs) in solution is an efficient route to fabricate complex hierarchical colloids which are of great importance for nanoencapsulation, microreactors, and biomimics. Herein, segmented wormlike micelles (SWMs) with controllable size are generated by the self-assembly of polystyrene- block-poly(4-vinyl pyridine) in microfluidic channel. Different from the assembly of BCPs off-chip at the same solution properties, it is found that the fabricated SWMs are kinetically controlled assemblies with thermodynamic metastable structures, which are formed by the orderly aggregation of preformed spherical micelles because of the fast mixing process in microfluidic channels. Moreover, by manipulating the total flow velocity of water and BCPs solution or their flow velocity ratio, both of the percentages of SWMs among the whole assemblies and their sizes can be effectively tuned. On the basis of electron microscopy and dynamic light scatting investigations, a product diagram of micellar morphologies associated to initial polymer concentration and flow velocity ratio of water/BCPs solution was constructed, which is important for the rational design and fabrication of complex hierarchical BCP colloids.

14.
Nature ; 501(7465): 107-11, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-23903657

RESUMO

Cancer research has been rightly and successfully focused on prevention, early detection, and identification of specific molecular targets that distinguish the malignant cells from the neighbouring benign cells. However, reducing lethal tissue injury caused by intensive chemoradiotherapy during treatment of late-stage metastatic cancers remains a key clinical challenge. Here we tested whether the induction of adult stem cells could repair chemoradiation-induced tissue injury and prolong overall survival in mice. We found that intestinal stem cells (ISCs) expressed Slit2 and its single-span transmembrane cell-surface receptor roundabout 1 (Robo1). Partial genetic deletion of Robo1 decreased ISC numbers and caused villus hypotrophy, whereas a Slit2 transgene increased ISC numbers and triggered villus hypertrophy. During lethal dosages of chemoradiation, administering a short pulse of R-spondin 1 (Rspo1; a Wnt agonist) plus Slit2 reduced ISC loss, mitigated gut impairment and protected animals from death, without concomitantly decreasing tumour sensitivity to chemotherapy. Therefore Rspo1 and Slit2 may act as therapeutic adjuvants to enhance host tolerance to aggressive chemoradiotherapy for eradicating metastatic cancers.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Intestinos/citologia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Trombospondinas/metabolismo , Animais , Linhagem da Célula , Proliferação de Células/efeitos dos fármacos , Feminino , Homeostase/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Intestinos/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/radioterapia , Neoplasias/patologia , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/farmacologia , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Regeneração/efeitos dos fármacos , Regeneração/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/efeitos da radiação , Taxa de Sobrevida , Trombospondinas/administração & dosagem , Trombospondinas/farmacologia , Proteínas Wnt/metabolismo , Proteínas Roundabout
15.
Soft Matter ; 13(14): 2634-2642, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28327712

RESUMO

Asymmetric vesicles with different inner and outer corona compositions are applicable in microreactors, drug delivery, and biomimics because of their unique functions in membrane permeability and protein localization. In this study, we develop a novel approach to construct asymmetric vesicles and demonstrate the first structural transformation of polymeric vesicles from symmetric to asymmetric membranes. Experimental results and Monte Carlo simulation results clearly reveal that increased intercorona repulsion and enhanced hydrophobic chain mobility are essential to realize this transformation. Moreover, similar transformation processes are observed where either HCl or NaOH is added to change the intercorona interaction. This finding indicates that the observed structural transformation is dominated by physical interactions rather than chemical environment. The constructed asymmetric vesicles can be selectively decorated with gold nanoparticles on the outer corona. This study introduces a novel approach to prepare asymmetric vesicles and provides insights into the mechanism underlying the structural transformation of polymeric vesicles from symmetric to asymmetric membranes.

16.
Zhongguo Zhong Yao Za Zhi ; 42(1): 182-186, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28945046

RESUMO

To analyze the medication features and the regularity of prescriptions of traditional Chinese medicine in treating patients with Qi-deficiency and blood-stasis syndrome of chronic heart failure based on modern literature. In this article, CNKI Chinese academic journal database, Wanfang Chinese academic journal database and VIP Chinese periodical database were all searched from January 2000 to December 2015 for the relevant literature on traditional Chinese medicine treatment for Qi-deficiency and blood-stasis syndrome of chronic heart failure. Then a normalized database was established for further data mining and analysis. Subsequently, the medication features and the regularity of prescriptions were mined by using traditional Chinese medicine inheritance support system(V2.5), association rules, improved mutual information algorithm, complex system entropy clustering and other mining methods. Finally, a total of 171 articles were included, involving 171 prescriptions, 140 kinds of herbs, with a total frequency of 1 772 for the herbs. As a result, 19 core prescriptions and 7 new prescriptions were mined. The most frequently used herbs included Huangqi(Astragali Radix), Danshen(Salviae Miltiorrhizae Radix et Rhizoma), Fuling(Poria), Renshen(Ginseng Radix et Rhizoma), Tinglizi(Semen Lepidii), Baizhu(Atractylodis Macrocephalae Rhizoma), and Guizhi(Cinnamomum Ramulus). The core prescriptions were composed of Huangqi(Astragali Radix), Danshen(Salviae Miltiorrhizae Radix et Rhizoma) and Fuling(Poria), etc. The high frequent herbs and core prescriptions not only highlight the medication features of Qi-invigorating and blood-circulating therapy, but also reflect the regularity of prescriptions of blood-circulating, Yang-warming, and urination-promoting therapy based on syndrome differentiation. Moreover, the mining of the new prescriptions provide new reference and inspiration for clinical treatment of various accompanying symptoms of chronic heart failure. In conclusion, this article provides new reference for traditional Chinese medicine in the treatment of chronic heart failure.


Assuntos
Mineração de Dados , Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Qi , Humanos , Medicina Tradicional Chinesa
17.
Biomed Environ Sci ; 28(4): 312-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25966759

RESUMO

A set of universal loop-mediated isothermal amplification (LAMP) primers targeting the fla gene was designed to detect Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) in human samples. The sensitivity of LAMP was 20 copies/reaction, and the assay did not detect false positives among 11 other related bacteria. A positive LAMP result was obtained for 9 of the 24 confirmed cases and for 12 of 94 suspected cases. The positive rate of LAMP was the same as that of nested PCR. The LAMP is a useful diagnostic method that can be developed for rapid detection of B. burgdorferi s.l. in human sera. Combination of the LAMP and nested PCR was more sensitive for detecting B. burgdorferi s.l. in human serum samples.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , DNA Bacteriano/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Grupo Borrelia Burgdorferi/genética , China , DNA Bacteriano/genética , Humanos , Doença de Lyme/diagnóstico , Sensibilidade e Especificidade
18.
Br J Nutr ; 111(9): 1536-48, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24502851

RESUMO

Ketoacids (KA) are known to improve muscle mass among patients with chronic kidney disease (CKD) on a low-protein diet (CKD-LPD), but the mechanism of its preventive effects on muscle atrophy still remains unclear. Since muscle atrophy in CKD may be attributable to the down-regulation of the Wnt7a/Akt/p70S6K pathway and the activation of the ubiquitin-proteasome system (UPS) and the apoptotic signalling pathway, a hypothesis can readily be drawn that KA supplementation improves muscle mass by up-regulating the Wnt7a/Akt/p70S6K pathway and counteracting the activation of the UPS and caspase-3-dependent apoptosis in the muscle of CKD-LPD rats. Rats with 5/6 nephrectomy were randomly divided into three groups, and fed with either 22 % protein (normal-protein diet; NPD), 6 % protein (LPD) or 5 % protein plus 1 % KA for 24 weeks. Sham-operated rats with NPD intake were used as the control. The results demonstrated that KA supplementation improved protein synthesis and increased related mediators such as Wnt7a, phosphorylated Akt and p70S6K in the muscle of CKD-LPD rats. It also inhibited protein degradation, withheld the increase in ubiquitin and its ligases MAFbx (muscle atrophy F-box) and MuRF1 (muscle ring finger-1) as well as attenuated proteasome activity in the muscle of CKD-LPD rats. Moreover, KA supplementation gave rise to a reduction in DNA fragment, cleaved caspase-3 and 14 kDa actin fragment via the down-regulation of the Bax:Bcl-2 ratio in the muscle of CKD-LPD rats. The beneficial effects unveiled herein further consolidate that KA may be a better therapeutic strategy for muscle atrophy in CKD-LPD.


Assuntos
Suplementos Nutricionais , Modelos Animais de Doenças , Cetoácidos/uso terapêutico , Músculo Esquelético/metabolismo , Atrofia Muscular/prevenção & controle , Proteínas Proto-Oncogênicas/agonistas , Insuficiência Renal Crônica/dietoterapia , Proteínas Wnt/agonistas , Animais , Apoptose , Dieta com Restrição de Proteínas/efeitos adversos , Regulação para Baixo , Masculino , Proteínas Musculares/biossíntese , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Nefrectomia/efeitos adversos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Proto-Oncogênicas/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/fisiopatologia , Transdução de Sinais , Ubiquitinação , Regulação para Cima , Proteínas Wnt/metabolismo
19.
Biomed Environ Sci ; 27(9): 665-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25256856

RESUMO

OBJECTIVE: Human Lyme Borreliosis (LB), which is caused by Borrelia burgdorferi sensu lato (B. burgdorferi), has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat (VNTR) analysis (MLVA) assay for the genotyping of Borrelia burgdorferi strains detected in China. METHODS: B. garinii PBi complete 904.246 kb chromosome and two plasmids (cp26 and lp54) were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means (UPGMA). RESULTS: We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto (B.b.s.s), B. garinii, B. afzelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index (HGI) of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. CONCLUSION: The MLVA protocol esytablished in this study is easy and can show strains' phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.


Assuntos
Grupo Borrelia Burgdorferi/genética , Técnicas de Genotipagem , China , Repetições Minissatélites
20.
Lancet Oncol ; 14(13): 1295-306, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24239208

RESUMO

BACKGROUND: Current staging methods do not accurately predict the risk of disease recurrence and benefit of adjuvant chemotherapy for patients who have had surgery for stage II colon cancer. We postulated that expression patterns of multiple microRNAs (miRNAs) could, if combined into a single model, improve postoperative risk stratification and prediction of chemotherapy benefit for these patients. METHOD: Using miRNA microarrays, we analysed 40 paired stage II colon cancer tumours and adjacent normal mucosa tissues, and identified 35 miRNAs that were differentially expressed between tumours and normal tissue. Using paraffin-embedded specimens from a further 138 patients with stage II colon cancer, we confirmed differential expression of these miRNAs using qRT-PCR. We then built a six-miRNA-based classifier using the LASSO Cox regression model, based on the association between the expression of every miRNA and the duration of individual patients' disease-free survival. We validated the prognostic and predictive accuracy of this classifier in both the internal testing group of 138 patients, and an external independent group of 460 patients. FINDINGS: Using the LASSO model, we built a classifier based on the six miRNAs: miR-21-5p, miR-20a-5p, miR-103a-3p, miR-106b-5p, miR-143-5p, and miR-215. Using this tool, we were able to classify patients between those at high risk of disease progression (high-risk group), and those at low risk of disease progression (low-risk group). Disease-free survival was significantly different between these groups in every set of patients. In the initial training group of patients, 5-year disease-free survival was 89% (95% CI 77·3-94·4) for the low-risk group, and 60% (46·3-71·0) for the high-risk group (hazard ratio [HR] 4·24, 95% CI 2·13-8·47; p<0·0001). In the internal testing set of patients, 5-year disease-free survival was 85% (95% CI 74·3-91·8) for the low-risk group, and 57% (42·8-68·5) for the high-risk group (HR 3·63, 1·86-7·01; p<0·0001), and in the independent validation set of patients, was 85% (79·6-89·0) for the low-risk group and 54% (46·4-61·1) for the high-risk group (HR 3·70, 2·56-5·35; p<0·0001). The six-miRNA-based classifier was an independent prognostic factor for, and had better prognostic value than, clinicopathological risk factors and mismatch repair status. In an ad-hoc analysis, the patients in the high-risk group were found to have a favourable response to adjuvant chemotherapy (HR 1·69, 1·17-2·45; p=0·0054). We developed two nomograms for clinical use that integrated the six-miRNA-based classifier and four clinicopathological risk factors to predict which patients might benefit from adjuvant chemotherapy after surgery for stage II colon cancer. CONCLUSION: Our six-miRNA-based classifier is a reliable prognostic and predictive tool for disease recurrence in patients with stage II colon cancer, and might be able to predict which patients benefit from adjuvant chemotherapy. It might facilitate patient counselling and individualise management of patients with this disease. FUNDING: Natural Science Foundation of China.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias do Colo/química , Neoplasias do Colo/patologia , MicroRNAs/análise , Idoso , Quimioterapia Adjuvante , China , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/cirurgia , Reparo de Erro de Pareamento de DNA , Progressão da Doença , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Nomogramas , Medicina de Precisão , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA