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1.
Angew Chem Int Ed Engl ; : e202402070, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664999

RESUMO

Electrochemical CO2 reduction reaction (CO2RR) offers a sustainable strategy for producing fuels and chemicals. However, it suffers from sluggish CO2 activation and slow water dissociation. In this work, we construct a (P-O)δ- modified In catalyst that exhibits high activity and selectivity in electrochemical CO2 reduction to formate. A combination of in situ characterizations and kinetic analyses indicate that (P-O)δ- has a strong interaction with K+(H2O)n, which effectively accelerates water dissociation to provide protons. In situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) measurements together with density functional theory (DFT) calculations disclose that (P-O)δ- modification leads to a higher valence state of In active site, thus promoting CO2 activation and HCOO* formation, while inhibiting competitive hydrogen evolution reaction (HER). As a result, the (P-O)δ- modified oxide-derived In catalyst exhibits excellent formate selectivity across a broad potential window with a formate Faradaic efficiency as high as 92.1 % at a partial current density of ~200 mA cm-2 and a cathodic potential of -1.2 V vs. RHE in an alkaline electrolyte.

2.
Nat Commun ; 15(1): 720, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267404

RESUMO

Developing in situ/operando spectroscopic techniques with high sensitivity and reproducibility is of great importance for mechanistic investigations of surface-mediated electrochemical reactions. Herein, we report the fabrication of highly ordered rhombic gold nanocube superlattices (GNSs) as substrates for surface-enhanced infrared absorption spectroscopy (SEIRAS) with significantly enhanced SEIRA effect, which can be controlled by manipulating the randomness of GNSs. Finite difference time domain simulations reveal that the electromagnetic effect accounts for the significantly improved spectroscopic vibrations on the GNSs. In situ SEIRAS results show that the vibrations of CO on the Cu2O surfaces have been enhanced by 2.4 ± 0.5 and 18.0 ± 1.3 times using GNSs as substrates compared to those on traditional chemically deposited gold films in acidic and neutral electrolytes, respectively. Combined with isotopic labeling experiments, the reaction mechanisms for C-C coupling of CO electroreduction on Cu-based catalysts are revealed using the GNSs substrates.

3.
Nat Commun ; 14(1): 8311, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097617

RESUMO

Understanding the structure-stability relationship of catalysts is imperative for the development of high-performance electrocatalytic devices. Herein, we utilize operando attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) to quantitatively monitor the evolution of Cu single-atom catalysts (SACs) during the electrochemical reduction of CO2 (CO2RR). Cu SACs are converted into 2-nm Cu nanoparticles through a reconstruction process during CO2RR. The evolution rate of Cu SACs is highly dependent on the substrates of the catalysts due to the coordination difference. Density functional theory calculations demonstrate that the stability of Cu SACs is highly dependent on their formation energy, which can be manipulated by controlling the affinity between Cu sites and substrates. This work highlights the use of operando ATR-SEIRAS to achieve mechanistic understanding of structure-stability relationship for long-term applications.

4.
Nat Commun ; 14(1): 6550, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848430

RESUMO

In this work, via engineering the conformation of cobalt active center in cobalt phthalocyanine molecular catalyst, the catalytic efficiency of electrochemical carbon monoxide reduction to methanol can be dramatically tuned. Based on a collection of experimental investigations and density functional theory calculations, it reveals that the electron rearrangement of the Co 3d orbitals of cobalt phthalocyanine from the low-spin state (S = 1/2) to the high-spin state (S = 3/2), induced by molecular conformation change, is responsible for the greatly enhanced CO reduction reaction performance. Operando attenuated total reflectance surface-enhanced infrared absorption spectroscopy measurements disclose accelerated hydrogenation of CORR intermediates, and kinetic isotope effect validates expedited proton-feeding rate over cobalt phthalocyanine with high-spin state. Further natural population analysis and density functional theory calculations demonstrate that the high spin Co2+ can enhance the electron backdonation via the dxz/dyz-2π* bond and weaken the C-O bonding in *CO, promoting hydrogenation of CORR intermediates.

5.
Angew Chem Int Ed Engl ; 62(44): e202311550, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37666796

RESUMO

Single-atom catalysts exhibit superior CO2 -to-CO catalytic activity, but poor kinetics of proton-coupled electron transfer (PCET) steps still limit the overall performance toward the industrial scale. Here, we constructed a Fe-P atom paired catalyst onto nitrogen doped graphitic layer (Fe1 /PNG) to accelerate PCET step. Fe1 /PNG delivers an industrial CO current of 1 A with FECO over 90 % at 2.5 V in a membrane-electrode assembly, overperforming the CO current of Fe1 /NG by more than 300 %. We also decrypted the synergistic effects of the P atom in the Fe-P atom pair using operando techniques and density functional theory, revealing that the P atom provides additional adsorption sites for accelerating water dissociation, boosting the hydrogenation of CO2 , and enhancing the activity of CO2 reduction. This atom-pair catalytic strategy can modulate multiple reactants and intermediates to break through the inherent limitations of single-atom catalysts.

6.
Int Immunopharmacol ; 124(Pt A): 110906, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690237

RESUMO

OBJECTIVES: Treatment of steroid-induced osteonecrosis of the femoral head (SIONFH) is challenging. Due to the limited understanding of its molecular mechanisms, investigating the potential mechanisms of ferroptosis will shed light on SIONFH and provide directions for treating this disease. METHODS: The GSE123568 dataset was utilized to apply various bioinformatics methodologies to identify ferroptosis-related hub genes (FRHGs). Subsequently, the importance of these genes and the reliability of the results were confirmed using protein data-independent acquisition (DIA) and cell experiments. Finally, we assessed the correlation between FRHG expression and immune cell infiltration. RESULTS: Thirty-one hub genes were identified and validated by constructing a protein-protein interaction network and subsequent screening using experimentally determined interactions. These 31 hub genes were enriched in immunity, the AMPK signaling pathway, and the Toll-like receptor signaling pathway. Next, we identified a diagnostic marker comprising two ferroptosis-related genes, NCF2 and SLC2A1. The differential expression of these two genes in healthy and necrotic regions was confirmed by protein DIA analysis. Cell experiments verified the link between FRHGs and ferroptosis and preliminarily explored the potential mechanism of the antioxidant vitexin in promoting osteogenic differentiation in cells. The diagnostic efficiency of these two markers was confirmed by receiver operating characteristic curve (ROC) curves, yielding an area under the curve of 1.0. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated enrichment of FRHGs in the superoxide anion and HIF-1 signaling pathways. A significant correlation was observed between FRHGs and various immune cell populations. CONCLUSION: NCF2 and SLC2A1 are promising ferroptosis-related diagnostic biomarkers of SIONFH. Concurrently, we embarked on a preliminary investigation to elucidate the potential mechanism underlying the promotion of osteogenic differentiation by the antioxidant vitexin. Moreover, these biomarkers are associated with distinct immune cell populations.

7.
Adv Mater ; : e2306480, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37555527

RESUMO

Constructing atomic catalytic pair emerges as an attractive strategy to achieve better catalytic performance. Herein, an atomic Ir1 ─P1 /NPG catalyst with asymmetric Ir─N2 P1 sites that delivers superb activity and selectivity for hydrogenation of various functionalized nitrostyrene is reported. In the hydrogenation reaction of 3-nitrostyrene, Ir1 ─P1 /NPG (NPG refers to N, P-codoped graphene) shows a turnover frequency of 1197 h-1 , while the reaction cannot occur over Ir1 /NG (NG refers to N-doped graphene). Compared to Ir1 /NG, the charge density of the Ir site in Ir1 ─P1 /NPG is greatly elevated, which is conducive to H2 dissociation. Moreover, as revealed by density functional theory calculations and poisoning experiments, the P site in Ir1 ─P1 /NPG is found able to bind nitrostyrene, while the neighboring Ir site provides H to reduce the nitro group in chemoselective hydrogenation of nitrostyrene. This work offers a successful example of establishing atomic catalytic pair for driving important chemical reactions, paving the way for the development of more advanced catalysts to further improve the catalytic performance.

8.
J Colloid Interface Sci ; 651: 18-26, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37536256

RESUMO

Single-atom catalysts supported on semiconductors can serve as active sites for efficient oxygen reduction to hydrogen peroxide (H2O2). However, researchers have long been puzzled by the lack of guidance on optimizing the performance of single-atom photocatalysts. In this study, we propose a versatile strategy that utilizes carbon vacancies to regulate the electronic configuration of antimony (Sb) atoms on carbon nitrides (C3N4). This strategy has been found to significantly enhance the photocatalytic production of H2O2. The H2O2 evolution rate of Sb single-atom on carbon vacancy-rich C3N4 (designated as Sb1/Cv-C3N4) is 5.369 mmol g-1h-1, which is 10.9 times higher than C3N4 alone. By combining experimental characterizations and density functional theory simulations, we reveal the strong electronic interaction between Sb atoms and carbon vacancy-rich C3N4. This interaction is capable for maintaining the electron-rich state of Sb atoms, facilitating efficient electron transfer to pauling-type absorbed oxygen, and ultimately enhancing the formation of *OOH intermediates. This innovative defect-engineering approach can manipulate the electronic configuration of single-atom catalysts, providing a new avenue to boost the photocatalytic oxygen reduction reaction towards H2O2 production.

9.
Int J Rheum Dis ; 26(9): 1686-1696, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37496262

RESUMO

BACKGROUND: Many studies have found that glucocorticoid (GC) combined with hydroxychloroquine (HCQ) has a good clinical effect in the treatment of systemic lupus erythematosus (SLE) rash, but there is no relevant systematic evaluation at present. The purpose of this study was to systematically evaluate and analyze the effectiveness and safety of GC combined with HCQ in the treatment of SLE rash. METHODS: Randomized controlled trials of GC combined with HCQ in the treatment of SLE rash were collected through computer retrieval of Cochrane Library, PubMed, Embase, CNKI, China Science and Technology Journal Database (VIP), Wanfang Data Knowledge Service Platform (Wanfang), and China Biology Medicine disc (CBM) since the establishment of the database. The main outcome indicators included clinical total effective rate, adverse reactions, SLE disease activity index (SLEDAI) score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complement 3 (C3). A meta-analysis was conducted using Review Manager 5.3 software. RESULTS: A total of 11 studies involving 809 patients (406 in the test group and 403 in the control group) were included in this article. The meta-analysis results showed that compared with the single use of GC, GC combined with HCQ could improve the clinical total effective rate in the treatment of SLE rash (odds ratio [OR] = 4.27, 95% confidence interval [CI] 2.50-7.30, p < .00001), and reduce the occurrence of adverse reactions (OR = 0.26, 95% CI 0.15-0.44, p < .00001); effectively reduce SLEDAI score (mean difference [MD] = 1.88, 95% CI 1.66-2.10, p < .00001) and ESR level (MD = 7.92, 95% CI 5.66-10.19, p < .00001); increase C3 level after treatment (MD = 0.36, 95% CI 0.32-0.41, p < .00001); and reduce CRP level (MD = 3.22, 95% CI 2.87-3.58, p < .00001), with statistically significant differences. CONCLUSION: Compared with the use of GC alone, GC combined with HCQ can improve the clinical effectiveness of SLE rash treatment, with a low incidence of adverse reactions and good clinical safety. However, the number and quality of studies included in this article were not high, so the findings need to be further verified by high-quality, multicenter randomized controlled trials.


Assuntos
Exantema , Lúpus Eritematoso Sistêmico , Humanos , Hidroxicloroquina/efeitos adversos , Glucocorticoides/efeitos adversos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/induzido quimicamente , Resultado do Tratamento , Exantema/induzido quimicamente , Exantema/diagnóstico , Exantema/tratamento farmacológico , Estudos Multicêntricos como Assunto
10.
Front Immunol ; 14: 1298683, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162672

RESUMO

Immunotherapy, notably chimeric antigen receptor (CAR) modified natural killer (NK) cell therapy, has shown exciting promise in the treatment of hematologic malignancies due to its unique advantages including fewer side effects, diverse activation mechanisms, and wide availability. However, CAR-NK cell therapies have demonstrated limited efficacy against solid tumors, primarily due to challenges posed by the solid tumor microenvironment. In contrast, radiotherapy, a well-established treatment modality, has been proven to modulate the tumor microenvironment and facilitate immune cell infiltration. With these observations, we hypothesize that a novel therapeutic strategy integrating CAR-NK cell therapy with radiotherapy could enhance the ability to treat solid tumors. This hypothesis aims to address the obstacles CAR-NK cell therapies face within the solid tumor microenvironment and explore the potential efficacy of their combination with radiotherapy. By capitalizing on the synergistic advantages of CAR-NK cell therapy and radiotherapy, we posit that this could lead to improved prognoses for patients with solid tumors.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Células Matadoras Naturais , Imunoterapia Adotiva , Neoplasias/radioterapia , Imunoterapia , Microambiente Tumoral
11.
J Int Med Res ; 50(11): 3000605221135458, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36352495

RESUMO

Solitary fibrous tumours (SFTs) usually occur at the pleura. Extrapleural sites, particularly giant extrapleural solitary fibromas, are more rarely observed in the clinic, and the clinical diagnosis and treatment of this disease is a focus of attention. Herein, the case of a 43-year-old male patient with giant presacral SFT successfully treated by open surgery, and with a final diagnosis confirmed by postoperative pathology and immunohistochemistry, is reported. The patient was followed-up regularly during 5 years after surgery, with no obvious surgical complications, and no tumour recurrence noted on pelvic magnetic resonance imaging. This case provides clinical information that may help in the diagnosis and treatment of complex SFT.


Assuntos
Recidiva Local de Neoplasia , Tumores Fibrosos Solitários , Masculino , Humanos , Adulto , Recidiva Local de Neoplasia/patologia , Tumores Fibrosos Solitários/diagnóstico por imagem , Tumores Fibrosos Solitários/cirurgia , Imuno-Histoquímica , Imageamento por Ressonância Magnética
12.
Int Orthop ; 46(4): 761-768, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34988620

RESUMO

BACKGROUND: Much research has focused on quantifying the bony characteristics of patients with developmental dysplasia of the hip (DDH). Far less attention, however, has been paid to muscle abnormalities around the hip such as those in the gluteus medius (GM). METHODS: We retrospectively examined clinical and imaging data, such as the age of onset and computed tomography (CT) findings, in 108 consecutive hips. Subjects for the control group were selected from our radiology database. Two readers independently evaluated the length (LGM), cross-sectional area (CSA), width (WGM), and thickness (TGM) of the GM and arm of GM (AGM) and angle of the GM activation (AOA) and bony parameters including the acetabulum-head index (AHI), lateral central edge angle (LCEA), acetabular index (AI), femoral offset (FO), and height of the rotation centre of femoral head (HCFH) among all cases using the imaging data. RESULTS: The patient group included 108 hips. The AGM, LGM, CSA, and TGM were lower in the DDH patients, while AOA was higher. However, there was no significant difference in the WGM between the two groups. Multiple linear regression analysis showed that AGM and AOA were independent factors affecting LCEA. The following regression equation was used: Y(LCEA) = 5.377 * X1 (AGM) - 0.310 * X2 (AOA) - 11.331. The mechanical characteristics of the GM and many bony parameters were significantly correlated (the AGM and AHI, LCEA, AI, FO, but not HCFH; AOA and AHI, LCEA, AI, but not FO or HCFH). The CSA was positively correlated with only HCFH. The rest were not statistical significance linear correlation. The multivariate regression results showed that the age of onset was positively correlated with AGM (r = 0.467). The regression equation used was Y = 9.0 * X (age of onset) - 11.4. CONCLUSION: We found difference in the morphological and mechanical characteristics of the GM between hips with DDH and hips of normal morphology. Of note, the mechanical characteristics of the GM were influenced by bony parameters in patients with DDH.


Assuntos
Luxação Congênita de Quadril , Luxação do Quadril , Acetábulo , Luxação Congênita de Quadril/complicações , Luxação Congênita de Quadril/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Osteotomia/métodos , Estudos Retrospectivos
13.
Int Orthop ; 46(3): 423-431, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34041582

RESUMO

PURPOSE: Our research developed a novel approach to quantitatively evaluate the boundary of necrotic lesions in osteonecrosis of the femoral head (ONFH) and to explore its diagnostic value in predicting bone collapse of the femoral head. METHODS: A retrospective cross-sectional study was conducted in our institution, and 146 hips (121 cases) identified as ONFH were recruited. The anterior and lateral boundaries of each enrolled subject were measured in standard anteroposterior (AP) view and frog-leg (FL) view of plain radiographic images, the intact rate of which was then calculated and presented as the anteroposterior view intact ratio (APIR) and frog-leg view intact ratio (FLIR), respectively. Univariate and multivariate logistic regression analyses were performed to identify risk factors for collapse. A receiver operating characteristic (ROC) curve analysis was performed to determine the sensitivity, specificity and cutoff value of the APIR and FLIR. A Kaplan-Meier (K-M) analysis was applied to calculate the survival rate of the femoral head, and bone collapse of the femoral head was regarded as the endpoint. RESULTS: Femoral head collapse was observed in 61 hips during the follow-up period. Patients with or without femoral head collapse were categorized into the collapse group and non-collapse group, respectively. The mean follow-up time was 3.7 years (2-9) for the collapse group and 7.7 years (5-20) for the non-collapse group. Univariate and multivariate logistic regression analysis and ROC analysis showed that APIR (< 25.61%) and FLIR (< 24.43%) were significantly associated with femoral head collapse. The K-M survival curves indicated that the overall survival rate of APIR (≥ 25.61%) was 94.8% at 7.5 years and 76.6% at 10 years, while that of FLIR (≥ 24.43%) was 87.3% at 7.5 years and ten years. CONCLUSION: The present study demonstrates that APIR and FLIR are of high diagnostic value in the early and middle stages of ONFH. APIR and FLIR can be used to predict the occurrence of femoral head collapse in patients with JIC classification types B and C1. The measurement of these two parameters in plain radiography images may contribute to the selection of a proper hip preservation strategy.


Assuntos
Necrose da Cabeça do Fêmur , Cabeça do Fêmur , Estudos Transversais , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/patologia , Humanos , Radiografia , Estudos Retrospectivos
14.
Biochem J ; 477(12): 2133-2151, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32484230

RESUMO

Oncomelania hupensis is the unique intermediate host of Schistosoma japonicum. As an irreplaceable prerequisite in the transmission and prevalence of schistosomiasis japonica, an in-depth study of this obligate host-parasite interaction can provide glimpse into the molecular events in the competition between schistosome infectivity and snail immune resistance. In previous studies, we identified a macrophage migration inhibitory factor (MIF) from O. hupensis (OhMIF), and showed that it was involved in the snail host immune response to the parasite S. japonicum. Here, we determined the crystal structure of OhMIF and revealed that there were distinct structural differences between the mammalian and O. hupensis MIFs. Noticeably, there was a projecting and structured C-terminus in OhMIF, which not only regulated the MIF's thermostability but was also critical in the activation of its tautomerase activity. Comparative studies between OhMIF and human MIF (hMIF) by analyzing the tautomerase activity, oxidoreductase activity, thermostability, interaction with the receptor CD74 and activation of the ERK signaling pathway demonstrated the functional differences between hMIF and OhMIF. Our data shed a species-specific light on structural, functional, and immunological characteristics of OhMIF and enrich the knowledge on the MIF family.


Assuntos
Isomerases/metabolismo , Sistema de Sinalização das MAP Quinases , Fatores Inibidores da Migração de Macrófagos/química , Fatores Inibidores da Migração de Macrófagos/metabolismo , Caramujos/fisiologia , Sequência de Aminoácidos , Animais , Domínio Catalítico , Conformação Proteica , Homologia de Sequência , Especificidade por Substrato
15.
ScientificWorldJournal ; 2014: 625754, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995358

RESUMO

Reliable information processing in cells requires high sensitivity to changes in the input signal but low sensitivity to random fluctuations in the transmitted signal. There are often many alternative biological circuits qualifying for this biological function. Distinguishing theses biological models and finding the most suitable one are essential, as such model ranking, by experimental evidence, will help to judge the support of the working hypotheses forming each model. Here, we employ the approximate Bayesian computation (ABC) method based on sequential Monte Carlo (SMC) to search for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. By systematically analyzing three-component circuits, we rank these biological circuits and identify three-basic-biological-motif buffering noise while maintaining sensitivity to long-term changes in input signals. We discuss in detail a particular implementation in control of nutrient homeostasis in yeast. The principal component analysis of the posterior provides insight into the nature of the reaction between nodes.


Assuntos
Teorema de Bayes , Simulação por Computador , Redes e Vias Metabólicas , Modelos Biológicos , Redes e Vias Metabólicas/fisiologia
16.
ScientificWorldJournal ; 2014: 380106, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25045731

RESUMO

Dynamic spectrum sharing has drawn intensive attention in cognitive radio networks. The secondary users are allowed to use the available spectrum to transmit data if the interference to the primary users is maintained at a low level. Cooperative transmission for secondary users can reduce the transmission power and thus improve the performance further. We study the joint subchannel pairing and power allocation problem in relay-based cognitive radio networks. The objective is to maximize the sum rate of the secondary user that is helped by an amplify-and-forward relay. The individual power constraints at the source and the relay, the subchannel pairing constraints, and the interference power constraints are considered. The problem under consideration is formulated as a mixed integer programming problem. By the dual decomposition method, a joint optimal subchannel pairing and power allocation algorithm is proposed. To reduce the computational complexity, two suboptimal algorithms are developed. Simulations have been conducted to verify the performance of the proposed algorithms in terms of sum rate and average running time under different conditions.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Humanos
17.
Patient Prefer Adherence ; 7: 905-13, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24049441

RESUMO

BACKGROUND: Breathing programs have been reported to have positive effects in alleviating symptoms and optimizing pulmonary function in patients with chronic obstructive pulmonary disease (COPD). However, patients with stable disease may drop out of such programs if they are not modified to the individual's exercise tolerance level, or if they are not easy to perform in the home. Little is known about the effectiveness of web-based home breathing programs for dyspnea. The purpose of this study was to evaluate the effectiveness of an online breathing program which included an animated diagram and video-guided instruction on pulmonary function, exercise capacity, and health-related quality of life in patients with COPD. METHODS: Sixty patients with stable COPD were randomized 1:1 to an experimental group (n = 30) or a control group (n = 30). Subjects in the experimental group trained for four months using an online program which included an animated diagram and video-guided instruction while the control group received conventional patient education on discharge from hospital. Forced expiratory volume, forced expiratory volume in one second (FEV1)/forced vital capacity (%), peak expiratory volume, six-minute walking distance test, and responses to the St George's Respiratory Questionnaire were assessed before and after the intervention. RESULTS: Patients in the two groups were well matched for demographic and clinical characteristics at baseline. All outcome measures showed significant improvement in the experimental group but not in the control group. CONCLUSION: The online training program resulted in improved pulmonary function, exercise capacity, and health status. Therefore, it is strongly recommended that patients with stable COPD be trained with such programs.

18.
Plant Cell Rep ; 27(3): 489-98, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18004571

RESUMO

In the present study, an efficient Agrobacterium-mediated gene transformation system was developed for soybean [Glycine max (L.) Merrill] based on the examinations of several factors affecting plant transformation efficiency. Increased transformation efficiencies were obtained when the soybean cotyledonary node were inoculated with the Agrobacterium inoculum added with 0.02% (v/v) surfactant (Silwet L-77). The applications of Silwet L-77 (0.02%) during infection and L-cysteine (600 mg l(-1)) during co-cultivation resulted in more significantly improved transformation efficiency than each of the two factors alone. The optimized temperature for infected explant co-cultivation was 22 degrees C. Regenerated transgenic shoots were selected and produced more efficiently with the modified selection scheme (initiation on shoot induction medium without hygromycin for 7 days, with 3 mg l(-1) hygromycin for 10 days, 5 mg l(-1) hygromycin for another 10 days, and elongation on shoot elongation medium with 8 mg l(-1) hygromycin). Using the optimized system, we obtained 145 morphologically normal and fertile independent transgenic plants in five important Chinese soybean varieties. The transformation efficacies ranged from 3.8 to 11.7%. Stable integration, expression and inheritance of the transgenes were confirmed by molecular and genetic analysis. T(1) plants were analyzed and transmission of transgenes to the T(1 )generation in a Mendelian fashion was verified. This optimized transformation system should be employed for efficient Agrobacterium-mediated soybean gene transformation.


Assuntos
Glycine max/genética , Rhizobium/genética , Transformação Genética/genética , Southern Blotting , Cinamatos/farmacologia , Cisteína/farmacologia , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimento , Temperatura , Transformação Genética/efeitos dos fármacos
19.
Mol Biotechnol ; 32(1): 55-63, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16382182

RESUMO

The removal of selected marker genes from transgenic plants is necessary to address biosafety concerns and to carry out further experiments with transgenic organisms. In the present study, the 12-amino-acid membrane translocation sequence (MTS) from the Kaposi fibroblast growth factor (FGF)-4 was used as a carrier to deliver enzymatically active Cre proteins into living plant cells, and to produce a site-specific DNA excision in transgenic rice plants. The process, which made cells permeable to Cre recombinase-mediated DNA recombination, circumvented the need to express Cre under spatiotemporal control and was proved to be a simple and efficient system to achieve marker-free transgenic plants. The ultimate aim of the present study is to develop commercial rice cultivars free from selected marker genes to hasten public acceptance of transgenic crops.


Assuntos
Deleção de Genes , Integrases/genética , Mutagênese Sítio-Dirigida/métodos , Oryza/genética , Proteínas Virais/genética , Southern Blotting , Células Cultivadas , Cinamatos/farmacologia , DNA de Plantas/genética , DNA de Plantas/metabolismo , Escherichia coli/genética , Fator 4 de Crescimento de Fibroblastos/genética , Expressão Gênica/genética , Engenharia Genética/métodos , Vetores Genéticos/genética , Glucuronidase/genética , Glucuronidase/metabolismo , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Integrases/metabolismo , Sinais de Localização Nuclear/genética , Oryza/citologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Recombinação Genética/efeitos dos fármacos , Recombinação Genética/genética , Proteínas Virais/metabolismo
20.
Artigo em Chinês | MEDLINE | ID: mdl-15840930

RESUMO

Great advances have been achieved in soybean transformation recently. Here, the main progress in soybean transformation and the protocol of some good systems are described. Some important factors affecting Agrobacterium-mediated soybean transformation are discussed.


Assuntos
Glycine max/genética , Plantas Geneticamente Modificadas/genética , Rhizobium/genética , Transformação Genética/genética
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