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1.
World J Surg Oncol ; 20(1): 192, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689233

RESUMO

BACKGROUND: Microwave ablation (MWA) is a potentially curative treatment for unresectable patients with hepatocellular carcinoma (HCC) ≤ 3 cm, while its therapeutic efficacy decreases significantly for HCC > 3cm. Previous studies have demonstrated that conventional transarterial chemoembolization (cTACE) combined with MWA (cTACE-MWA) may improve local tumor control rate and reduce the recurrence rate for HCC > 3cm. However, there have been few study designs to analyze the clinical efficacy of cTACE-MWA for medium-sized HCC (3-5cm). Therefore, this study aims to compare the clinical efficacy and safety of cTACE-MWA with cTACE alone for a single medium-sized HCC of 3-5 cm in diameter. METHODS: We retrospectively investigate the data of 90 patients with a single medium-sized HCC who were referred to our hospital and underwent cTACE-MWA or cTACE alone from December 2017 to March 2020. Then, patients were identified with propensity score-matched (1:1). The local tumor response to treatment and time to progression (TTP) were compared using mRECIST criteria between the cTACE-MWA group and the cTACE group. RESULTS: A total of 42 patients were included after matching (cTACE-MWA: 21; cTACE: 21). Comparing with cTACE, cTACE-MWA demonstrate significantly better local tumor control (ORR: 95.2% vs 61.9%, p = 0.02; DCR: 95.2% vs 66.7%, p = 0.045) and TTP (median 19.8 months vs 6.8 months, p < 0.001). The 1- and 2-year cumulative probabilities of OS were 100% and 95% in the cTACE-MWA group, which were significantly higher than those in the cTACE group (95% and 76%) (p = 0.032). Multivariate Cox regression analysis illustrates that cTACE-MWA was associated with better TTP (hazard ratio, 0.28; 95% CI: 0.1, 0.76; p = 0.012), but tumor size was associated with worse TTP (hazard ratio, 1.71; 95% CI: 1.01, 2.89; p = 0.045). CONCLUSIONS: cTACE followed by MWA improved TTP and OS in patients with a single medium-sized HCC, and no major complication was observed in this study.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
2.
J Fungi (Basel) ; 7(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34829220

RESUMO

Auricularia has a worldwide distribution and is very important due to its edibility and medicinal properties. Morphological examinations and multi-gene phylogenetic analyses of 277 samples from 35 countries in Asia, Europe, North and South America, Africa, and Oceania were carried out. Phylogenetic analyses were based on ITS, nLSU, rpb1, and rpb2 sequences using methods of Maximum Likelihood and Bayesian Inference analyses. According to the morphological and/or molecular characters, 37 Auricularia species were identified. Ten new species, A. camposii and A. novozealandica in the A. cornea complex, A. australiana, A. conferta, A. lateralis, A. pilosa and A. sinodelicata in the A. delicata complex, A. africana, A. srilankensis, and A. submesenterica in the A. mesenterica complex, are described. The two known species A. pusio and A. tremellosa, respectively belonging to the A. mesenterica complex and the A. delicata complex, are redefined, while A. angiospermarum, belonging to the A. auricula-judae complex, is validated. The morphological characters, photos, ecological traits, hosts and geographical distributions of those 37 species are outlined and discussed. Morphological differences and phylogenetic relations of species in five Auricularia morphological complexes (the A. auricula-judae, the A. cornea, the A. delicata, the A. fuscosuccinea and the A. mesenterica complexes) are elaborated. Synopsis data on comparisons of species in the five complexes are provided. An identification key for the accepted 37 species is proposed.

3.
MycoKeys ; 82: 33-56, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393591

RESUMO

Samples of species close to Tremellafibulifera from China and Brazil are studied, and T.fibulifera is confirmed as a species complex including nine species. Five known species (T.cheejenii, T.fibulifera s.s., T. "neofibulifera", T.lloydiae-candidae and T.olens) and four new species (T.australe, T.guangxiensis, T.latispora and T.subfibulifera) in the complex are recognized based on morphological characteristics, molecular evidence, and geographic distribution. Sequences of eight species of the complex were included in the phylogenetic analyses because T.olens lacks molecular data. The phylogenetic analyses were performed by a combined sequence dataset of the internal transcribed spacer (ITS) and the partial nuclear large subunit rDNA (nLSU), and a combined sequence dataset of the ITS, partial nLSU, the small subunit mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α (TEF1), the largest and second largest subunits of RNA polymerase II (RPB1 and RPB2). The eight species formed eight independent lineages with robust support in phylogenies based on both datasets. Illustrated description of the six species including Tremellafibulifera s.s., T. "neofibulifera" and four new species, and discussions with their related species, are provided. A table of the comparison of the important characteristics of nine species in the T.fibulifera complex and a key to the whitish species in Tremella s.s. are provided.

4.
Nanotechnology ; 31(33): 335717, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32375129

RESUMO

N-doped carbon-based materials are crucial electrically conductive additives and non-metal electrocatalysts for the oxygen reduction reaction. At present, many pieces of research are focused on the effects of micropore, mesopore and hierarchical pore structure on the catalytic activity, however, there are few works concerning the role of large-dimension through-hole structure. Hence, in this work, we prepare two kinds of carbon materials with large through-hole structure, i.e. N-doped carbon hollow-spheres and hollow-tubes, as the oxygen reduction catalysts. The synthesis follows template-free morphology-controlled pyrolysis, which is more convenient than the preparation of conventional N-doped nanotubes and graphene. The resultant N-doped carbon hollow-spheres and hollow-tubes evidently enhanced their ORR catalytic activity, remarkable long-term stability and methanol resistance. The large-dimension through-hole structure is found to account for the increase in mass transfer.

5.
ACS Appl Mater Interfaces ; 11(34): 31346-31355, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31381290

RESUMO

The present work is focused on developing external stress-free two-way triple shape memory polymers (SMPs). Accordingly, a series of innovative approaches are proposed for the material design and preparation. Polyurethane prepolymers carrying crystalline polytetrahydrofuran (PTMEG) and poly(ε-caprolactone) (PCL) as the switching phases are respectively synthesized in advance and then cross-linked to produce the target material. The stepwise method is believed to be conducive to manipulation of the relative contribution of PCL and PTMEG. Moreover, the chain extender, 2-amino-5-(2-hydroxyethyl)-6-methylpyrimidin-4-ol (UPy), is incorporated to establish hydrogen bonds among the macromolecules. By straightforward stretching treatment at different temperatures, the hydrogen bond networks are successfully converted into an internal stress provider, which overcomes the challenge of stress relaxation of the melted low melting temperature polymer (i.e., PTMEG) and increases the efficiency of stress transfer. Meanwhile, the contraction force of the switching phases is tuned to match the internal tensile stress. As a result, the internal stress provider can closely collaborate with melting/recrystallization of the crystalline domains, leading to the repeated multiple shape memory effects. The cross-linked polyurethane is thus able to reversibly morph among three shapes and displays its potentials as soft robot and actuator. The strategy reported here has the advantages of easily accessible raw materials, simple reaction, and facile programing/deprograming/reprograming, so that it possesses wide applicability.

6.
ACS Macro Lett ; 8(9): 1141-1146, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-35619451

RESUMO

Two simple methods are proposed to respectively impart external force-free reversible shape memory effect to commercial polyolefins: ultrahigh molecular weight polyethylene (UHMWPE) and polypropylene (PP). The key issues lie in the utilization of the partially entangled molecular chains of UHMWPE and the medium crystalline phases of PP as the reversible internal stress providers. The acquired reversible shape memory effect further proves to be applicable for assisting repeatedly self-healing of wider cracks. Compared to the conventional approaches, which used to introduce cross-linkages into the target materials, the present ones only need physical treatment, so that the valuable thermoplasticity of polyolefins is retained. This work can be regarded as an example of the concept "physically converting instead of chemically modifying" for the preparation of functional polymeric materials based on market available plastics.

7.
ACS Appl Mater Interfaces ; 10(44): 38538-38546, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30284805

RESUMO

To enable repeated intrinsic self-healing of wider cracks in polymers, a proof-of-concept approach is verified in the present work. It operates through two-way shape memory effect (SME)-aided intrinsic self-healing. Accordingly, a reversible C-ON bond is introduced into the main chain of crosslinked polyurethane (PU) containing an elastomeric dispersed phase (styrene-butadiene-styrene block copolymer, SBS). The PU/SBS blend was developed by the authors recently, and proved to possess an external stress-free two-way SME after programming. As a result, the thermal retractility offered by the SME coupled with the reversible C-ON bonds can be used for successive crack closure and remending based on synchronous fission/radical recombination of C-ON bonds. Moreover, multiwalled carbon nanotubes are incorporated to impart electrical conductivity to the insulating polymer. Repeated autonomic healing of wider cracks is thus achieved through narrowing of cracks followed by chemical rebonding under self-regulating Joule heating. No additional programming is needed after each healing event, which is superior to one-way SME-assisted self-healing. The outcomes set an example of integrating different stimuli-responsivities into single materials.

8.
Macromol Rapid Commun ; 39(12): e1700714, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29749065

RESUMO

Development of two-way shape memory polymers that operate free of external force remains a great challenge. Here, the design criteria for this type of material are proposed, deriving a novel fabrication strategy accordingly, which employs conventional crosslinked polyurethane (PU) containing crystalline poly(ε-caprolactone) (PCL) as the proof-of-concept material. Having been simply trained by stretching and thermal treatment without additional ingredients and chemicals, the PU is coupled with a two-way shape memory effect. The core advancement of this study lies in the successful conversion of the inherent hydrogen bond network, which is often the easiest to overlook, into an internal stress provider. The temperature-dependent reversible melting/recrystallization of the crystalline phases elaborately works with the tensed hydrogen bond network, leading to implementation of the two-way shape memory effect. An average reversible strain of as high as ≈20% along the stretch direction is obtained through cooperation adjustment of chemical crosslinking density, crystallinity, and concentration of hydrogen bonds. Meanwhile, the highest internal tension offered by the hydrogen bond network is determined to be 0.10 MPa. Owing to the great convenience characterized by material selection, preparation, programming, and application, the current work may open up an avenue for production and usage of the smart material.


Assuntos
Materiais Biocompatíveis/química , Poliésteres/química , Polímeros/química , Poliuretanos/química , Materiais Biocompatíveis/síntese química , Cristalização , Ligação de Hidrogênio , Estrutura Molecular , Polímeros/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
9.
Macromol Rapid Commun ; 38(16)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28627040

RESUMO

The present communication reports a novel strategy to fabricate reversible shape-memory polymer that operates without the aid of external force on the basis of a two-phase structure design. The proof-of-concept material, crosslinked styrene-butadiene-styrene block copolymer (SBS, dispersed phase)/polycaprolactone-based polyurethane (PU, continuous phase) blend, possesses a closely connected microphase separation structure. That is, SBS phases are chemically bonded to crosslinked PU by means of a single crosslinking agent and two-step crosslinking process for increasing integrity of the system. Miscibility between components in the blend is no longer critical by taking advantage of the reactive blending technique. It is found that a suitable programming leads to compressed SBS, which serves as internal expansion stress provider as a result. The desired two-way shape-memory effect is realized by the joint action of the temperature-induced reversible opposite directional deformabilities of the crystalline phase of PU and compressed SBS, accompanying melting and orientated recrystallization of the former. Owing to the broadness of material selection and manufacturing convenience, the proposed approach opens an avenue toward mass production and application of the smart polymer.


Assuntos
Técnicas de Química Analítica , Polímeros/síntese química , Elastômeros , Fenômenos Mecânicos , Poliuretanos/química , Estirenos/química , Temperatura
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