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1.
Artigo em Inglês | MEDLINE | ID: mdl-31729821

RESUMO

On-surface synthesis offers a versatile approach to fabricate novel carbon-based nanostructures that cannot be obtained via conventional solution chemistry. Within the family of such nanomaterials, graphene nanoribbons (GNRs) hold a privileged position due to their high potential for a variety of applications. One of the key issues for their application in molecular electronics lies in the fine-tuning of their electronic properties through structural modifications, such as heteroatom doping or the incorporation of non-benzenoid rings. In this context, the covalent fusion of GNRs and porphyrins (Pors) represents a highly appealing strategy. In this work, we present the selective on-surface synthesis of a Por-GNR hybrid, which consists of two Pors connected by a short GNR segment. The atomically precise structure of the obtained dimer has been unambiguously characterized by bond-resolved scanning tunneling microscopy (STM) and noncontact atomic force microscopy (nc-AFM). The electronic properties of the dimer have been investigated by STS in combination with DFT calculations, which reveals a low electronic gap of 0.4 eV.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31684720

RESUMO

In this study, we demonstrated the Au-catalyzed growth of free-standing defect-free zinc-blende structured InAs nanobelts on the GaAs {111}B substrate by molecular beam epitaxy. Through detailed morphological, chemical, and structural characterizations using advanced electron microscopy, it was found that the nanobelts grew along the ⟨001̅⟩ direction, induced by Au catalysts via vapor-solid-solid mechanism, with features of {001̅} catalyst/nanobelt interfaces and extensive {11̅0} surfaces. The formation of the belt-shaped morphology of our nanostructures resulted from a faster lateral growth rate along the ±[110] direction than that along the ±[11̅0] direction, driven by polarity. This study provides insights into understanding the growth of free-standing zinc-blende structured <001̅> InAs nanobelts.

3.
PLoS One ; 14(11): e0224869, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31710631

RESUMO

BACKGROUND: Self-management is the cornerstone of diabetes care, however, despite the numerous recommendations available for self-management, type-2 diabetes mellitus (T2DM) patients' performance is suboptimal in China. This study aimed to explore the association between self-efficacy and self-management behaviors among Chinese T2DM patients, which might provide evidence to inform effective self-management interventions for these patients. METHODS: A cross-sectional survey was conducted using a multi-stage stratified randomized sampling in Shandong Province, China. The Diabetes Empowerment Scale-Short Form (DES-SF) was used to measure patients' self-efficacy to manage diabetes. Latent class analysis (LCA) was used to explore the observed classes of self-management behaviors (dietary control, physical exercise, regular medication and self-monitoring of blood glucose). A two-class solution for self-management behaviors was tested to be the fittest based on LCA; we labelled active and inactive self-management groups. Univariate and multivariate logistic regression analysis were used to examine the associations between self-efficacy and self-management behaviors. RESULTS: A total of 2166 T2DM patients were included in the analysis. The mean DES-SF score was 31.9 (standard deviation: 5.2). The estimated proportions of T2DM in the active and inactive groups were 54.8% and 45.2%, respectively. The multivariate logistic regression showed that higher DES-SF score was significantly associated with higher possibility of active self-management behaviors (odds ratio = 1.06; 95% confidence interval: 1.04-1.08). CONCLUSIONS: Self-efficacy in managing diabetes is associated with self-management behaviors among Chinese T2DM patients. To improve self-management behaviors, multiple strategies should be conducted to improve patients' self-efficacy.

4.
Bioresour Technol ; 296: 122288, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31678706

RESUMO

Magnetic biosorbents with specific morphological and molecular structure (PMCCs) were designed for the removal of ciprofloxacin (CIP) from water. Radical polymerization method was applied to immobilize the designed polymer brushes onto core-shell shaped magnetic microspheres to fabricate PMCCs. PMCCs exhibited a maximum adsorption capacity of 527.93 mg·g-1, which is much higher than reported adsorbents, owing to the complete stretch of polymer brushes and increased active sites as well as enhanced interaction. The investigation on the adsorption behavior of PMCCs for CIP manifested that CIP adsorption well fitted the Langmuir isotherm model and pseudo-second-order kinetic model. The calculated thermodynamic parameters suggested that CIP adsorption onto PMCCs was spontaneous and exothermic. Further recycling experiments showed a loss of less than 20% in the CIP adsorption capacity after five times, demonstrating the reusability of the as-designed biosorbents.

5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(5): 673-677, 2019 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-31699199

RESUMO

Objective To approach the discordance of estrogen receptor(ER),progesterone receptor(PR),Cerb-B2,Ki-67 index and P53 expressions between primary and regional or distant recurrent lesions in recurrent or metastatic breast cancer patients.Methods Clinical and pathological data of 56 recurrent or metastatic breast cancer patients who were treated in Peking Union Medical College Hospital from January 2001 to February 2015 were retrospectively analyzed.The changes in the expressions of ER,PR,Cerb-B2,Ki-67 index,and P53 status were analyzed.Results The hormone receptor positive rate between primary tumor and recurrent or metastatic sites decreased from 60.7% to 57.1% for ER and from 55.4% to 44.6% for PR,respectively.Changes in hormone receptor status were seen at the rate of 12.5%(7/56)and 16.1%(9/56)for ER and PR,respectively.Cerb-B2 receptor positive rate increased from 19.1% to 29.5% and the discordance rate was 9.1%(4/44).The discordance rate of Ki-67 index was 24.5%(12/49).The P53 receptor positive rate increased from 37.5% to 55.6% and the discordance rate was 13.3%(6/45).Conclusion Although the relevant rules of above changes are still controversial,these findings still have great clinical significance for making effective treatment decisions of recurrent or metastatic breast cancer.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31617958

RESUMO

Autologous bone grafts constitute the second most transplanted tissue in medicine today. The viability, and consequently the osteogenic capacity, of an autograft is directly impacted by the interval between harvest and transplantation, but how the temperature and the solution in which the graft is held intraoperatively affect viability is not clear. Using a syngeneic mouse model and in vivo bone-forming assays, these variables were tested for their effects on programmed cell death, osteoprogenitor cell proliferation, and the ability of the autograft to ultimately produce new bone in an ectopic site. Based on these results, the intraoperative treatment with a WNT protein therapeutic was tested for its effects on the viability and osteogenic capacity of an autograft. Viability, programmed cell death, mitotic activity, osteogenic protein expression, and bone-forming capacity were assessed. Experimental results demonstrated that the osteogenic capacity of an autograft is significantly improved by intraoperative storage in L-WNT3A at physiological temperature.

8.
Chem Commun (Camb) ; 55(89): 13466-13469, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31647065

RESUMO

Azulene, the smallest neutral nonalternant aromatic hydrocarbon, serves not only as a prototype for fundamental studies but also as a versatile building block for functional materials because of its unique opto(electronic) properties. Here, we report the on-surface synthesis and characterization of the homopolymer of azulene connected exclusively at the 2,6-positions using 2,6-diiodoazulene as the monomer precursor. As an intermediate to the formation of polyazulene, a gold-(2,6-azulenylene) chain is observed.

9.
Int J Med Inform ; 132: 103985, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31627032

RESUMO

OBJECTIVE: Breast cancer is the most common malignant tumor among women. The diagnosis and treatment information of breast cancer patients is abundant in multiple types of clinical fields, including clinicopathological data, genotype and phenotype information, treatment information, and prognosis information. However, current studies are mainly focused on extracting information from one specific type of clinical field. This study defines a comprehensive information model to represent the whole-course clinical information of patients. Furthermore, deep learning approaches are used to extract the concepts and their attributes from clinical breast cancer documents by fine-tuning pretrained Bidirectional Encoder Representations from Transformers (BERT) language models. MATERIALS AND METHODS: The clinical corpus that was used in this study was from one 3A cancer hospital in China, consisting of the encounter notes, operation records, pathology notes, radiology notes, progress notes and discharge summaries of 100 breast cancer patients. Our system consists of two components: a named entity recognition (NER) component and a relation recognition component. For each component, we implemented deep learning-based approaches by fine-tuning BERT, which outperformed other state-of-the-art methods on multiple natural language processing (NLP) tasks. A clinical language model is first pretrained using BERT on a large-scale unlabeled corpus of Chinese clinical text. For NER, the context embeddings that were pretrained using BERT were used as the input features of the Bi-LSTM-CRF (Bidirectional long-short-memory-conditional random fields) model and were fine-tuned using the annotated breast cancer notes. Furthermore, we proposed an approach to fine-tune BERT for relation extraction. It was considered to be a classification problem in which the two entities that were mentioned in the input sentence were replaced with their semantic types. RESULTS: Our best-performing system achieved F1 scores of 93.53% for the NER and 96.73% for the relation extraction. Additional evaluations showed that the deep learning-based approaches that fine-tuned BERT did outperform the traditional Bi-LSTM-CRF and CRF machine learning algorithms in NER and the attention-Bi-LSTM and SVM (support vector machines) algorithms in relation recognition. CONCLUSION: In this study, we developed a deep learning approach that fine-tuned BERT to extract the breast cancer concepts and their attributes. It demonstrated its superior performance compared to traditional machine learning algorithms, thus supporting its uses in broader NER and relation extraction tasks in the medical domain.

10.
Lancet ; 394(10204): 1192-1204, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31571602

RESUMO

In 2009, China launched a major health-care reform and pledged to provide all citizens with equal access to basic health care with reasonable quality and financial risk protection. The government has since quadrupled its funding for health. The reform's first phase (2009-11) emphasised expanding social health insurance coverage for all and strengthening infrastructure. The second phase (2012 onwards) prioritised reforming its health-care delivery system through: (1) systemic reform of public hospitals by removing mark-up for drug sales, adjusting fee schedules, and reforming provider payment and governance structures; and (2) overhaul of its hospital-centric and treatment-based delivery system. In the past 10 years, China has made substantial progress in improving equal access to care and enhancing financial protection, especially for people of a lower socioeconomic status. However, gaps remain in quality of care, control of non-communicable diseases (NCDs), efficiency in delivery, control of health expenditures, and public satisfaction. To meet the needs of China's ageing population that is facing an increased NCD burden, we recommend leveraging strategic purchasing, information technology, and local pilots to build a primary health-care (PHC)-based integrated delivery system by aligning the incentives and governance of hospitals and PHC systems, improving the quality of PHC providers, and educating the public on the value of prevention and health maintenance.


Assuntos
Assistência à Saúde , Reforma dos Serviços de Saúde , Acesso aos Serviços de Saúde , Doenças não Transmissíveis/prevenção & controle , Atenção Primária à Saúde , Cobertura Universal do Seguro de Saúde , China , Educação em Saúde , Gastos em Saúde , Política de Saúde , Humanos , Doenças não Transmissíveis/terapia
11.
BMC Cancer ; 19(1): 939, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604469

RESUMO

BACKGROUND: This preliminary study aimed to examine the feasibility of sentinel lymph node biopsy (SLNB) using contrast-enhanced ultrasound (CEUS) vs. indocyanine green fluorescence (ICG), combined with blue dye in patients with breast cancer. METHODS: This was a retrospective study of consecutive female patients with invasive stage I-III (based on pre-operative physical examination and imaging) primary breast cancer at the Peking Union Medical College Hospital between 01/2013 and 01/2015 who underwent preoperative SLNB by ICG + blue dye or CEUS + blue dye. The numbers of detected SLNs, detection rates, and recurrence-free survival (RFS) rates were compared between the two groups. RESULTS: A total of 443 patients were included. The detection rates of SLNs in the CEUS + blue dye and ICG + blue dye groups were 98.4 and 98.1%, respectively (P = 0.814). The average numbers of SLNs detected per patient showed no significant difference between the two groups (3.06 ± 1.33 and 3.12 ± 1.31 in the CEUS + blue dye and ICG + blue dye groups, respectively; P = 0.659). After a median follow-up of 46 months, five patients in the CEUS + blue dye group and 15 in the ICG + blue dye group had recurrence. RFS rates showed no significant difference (P = 0.55). CONCLUSION: This preliminary study suggests that CEUS + blue dye and ICG + blue dye are both feasible for SLN detection in breast cancer.

12.
Environ Health Perspect ; 127(10): 107009, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31642700

RESUMO

BACKGROUND: The rapidly increasing dissemination of carbapenem-resistant Enterobacteriaceae (CRE) in both humans and animals poses a global threat to public health. However, the transmission of CRE between humans and animals has not yet been well studied. OBJECTIVES: We investigated the prevalence, risk factors, and drivers of CRE transmission between humans and their backyard animals in rural China. METHODS: We conducted a comprehensive sampling strategy in 12 villages in Shandong, China. Using the household [residents and their backyard animals (farm and companion animals)] as a single surveillance unit, we assessed the prevalence of CRE at the household level and examined the factors associated with CRE carriage through a detailed questionnaire. Genetic relationships among human- and animal-derived CRE were assessed using whole-genome sequencing-based molecular methods. RESULTS: A total of 88 New Delhi metallo-ß-lactamases-type carbapenem-resistant Escherichia coli (NDM-EC), including 17 from humans, 44 from pigs, 12 from chickens, 1 from cattle, and 2 from dogs, were isolated from 65 of the 746 households examined. The remaining 12 NDM-EC were from flies in the immediate backyard environment. The NDM-EC colonization in households was significantly associated with a) the number of species of backyard animals raised/kept in the same household, and b) the use of human and/or animal feces as fertilizer. Discriminant analysis of principal components (DAPC) revealed that a large proportion of the core genomes of the NDM-EC belonged to strains from hosts other than their own, and several human isolates shared closely related core single-nucleotide polymorphisms and blaNDM genetic contexts with isolates from backyard animals. CONCLUSIONS: To our knowledge, we are the first to report evidence of direct transmission of NDM-EC between humans and animals. Given the rise of NDM-EC in community and hospital infections, combating NDM-EC transmission in backyard farm systems is needed. https://doi.org/10.1289/EHP5251.

13.
J Hazard Mater ; 384: 121262, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31586922

RESUMO

In the case of a sharp increase in the price of dyes, the dyes concentration of in wastewater is important for environmental protection and industrial costs reduction. In this study, we grafted single-layer amino groups onto the surface of the hollow glass microspheres by a two-step simple synthesis, and the anionic dyes adsorption process reaches equilibrium within 10 min. The as-synthesized adsorbent has self-floating ability to achieve high-efficiency surface solid-liquid separation with water. SEM, EDS, SBET, FT-IR, XPS, TGA characterizations results demonstrated the successful grafting of amino groups and the important role of the pretreatment process in the two-step synthesis. The results of adsorption isotherms and kinetics show the adsorption process belongs to single-layer adsorption with equal adsorption sites, and the adsorption capacities for acid orange 7 and amaranth reach 428.99 mg g-1 and 145.62 mg g-1, respectively. Regeneration of the adsorbent and concentration of the dye solutions can be achieved by dispersing the separated adsorbent in alkaline solution, the maximum concentrated concentration of acid orange 7 and amaranth was 6321.57 mg L-1 and 2431.84 mg L-1, respectively. This study provides new insights for the solid-liquid separation of water treatment agents and the resource regenerating of dyeing wastewater.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31652012

RESUMO

Red yeast rice has been utilized for colouring food, brewing wine and preserving meat, which is also used as a folk medicine for centuries. In this study, a water-soluble non-starch polysaccharide from red yeast rice (RYRP) was extracted by using ultrasonic-assisted extraction method. By using Box-Behnken design (BBD) to optimize the parameters for extracting the RYRP, the maximum extraction yield (3.37%±0.78%) was obtained under the optimal extraction conditions as follows: ratio of water to raw material (40 mL/g), extraction temperature (62°C), extraction time (75 min) and ultrasonic power (200 W). Moreover, monosaccharide composition analysis showed that RYRP was consisted of mannose, glucosamine, glucose and galactose with a molar ratio of 0.152:0.015:1:0.149. The molecular weight distribution analysis showed that the average molecular weight of the RYRP fraction was about 3.49 × 103 Da. Furthermore, RYRP exhibited significant antioxidant activities in vitro and the gastrointestinal-protective effect in vivo using gastrointestinal disorders (GD) model mice. RYRP could be explored as a potential source in the pharmaceutical and functional food industries.

17.
J Cell Physiol ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31612481

RESUMO

The aim of this study was to identify key genes related to the progression of colon adenocarcinoma (COAD), and to investigate the regulatory network of hub genes and transcription factors (TFs). Dataset GSE20916 including 44 normal colon, 55 adenoma, and 36 adenocarcinoma tissue samples was used to construct co-expression networks via weighted gene co-expression network. Gene Ontology annotation and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis for the objective module were performed using the online Database for Annotation, Visualization and Integrated Discovery. Hub genes were identified by taking the intersection of differentially expressed genes between dataset GSE20916 and GSE39582 and validated using The Cancer Genome Atlas (TCGA) database. The correlations between microRNA (miRNA) and hub genes were analyzed using the online website StarBase. Cytoscape was used to establish a regulatory network of TF-miRNA-target gene. We found that the orange module was a key module related to the tumor progression in COAD. In datasets GSE20916 and GSE39582, a total of eight genes (BGN, SULF1, COL1A1, FAP, THBS2, CTHRC1, COL5A2, and COL1A2) were selected, which were closely related with patients' survivals in TCGA database and dataset GSE20916. COAD patients with higher expressions of each hub gene had a worse prognosis than those with lower expressions. A regulatory network of TF-miRNA-target gene with 144 TFs, 26 miRNAs, and 7 hub genes was established, including model KLF11-miR149-BGN, TCEAL6-miR29B2-COL1A1, and TCEAL6-miR29B2-COL1A2. In conclusion, during the progression of COAD, eight core genes (BGN, SULF1, COL1A1, FAP, THBS2, CTHRC1, COL5A2, and COL1A2) play vital roles. Regulatory networks of TF-miRNA-target gene can help to understand the disease progression and optimize treatment strategy.

18.
ACS Nano ; 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31573799

RESUMO

Graphene nanoribbons (GNRs) have attracted considerable interest, as their atomically tunable structure makes them promising candidates for future electronic devices. However, obtaining detailed information about the length of GNRs has been challenging and typically relies on low-temperature scanning tunneling microscopy. Such methods are ill-suited for practical device application and characterization. In contrast, Raman spectroscopy is a sensitive method for the characterization of GNRs, in particular for investigating their width and structure. Here, we report on a length-dependent, Raman-active low-energy vibrational mode that is present in atomically precise, bottom-up-synthesized armchair graphene nanoribbons (AGNRs). Our Raman study demonstrates that this mode is present in all families of AGNRs and provides information on their length. Our spectroscopic findings are corroborated by scanning tunneling microscopy images and supported by first-principles calculations that allow us to attribute this mode to a longitudinal acoustic phonon. Finally, we show that this mode is a sensitive probe for the overall structural integrity of the ribbons and their interaction with technologically relevant substrates.

19.
Int J Biol Macromol ; 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31593736

RESUMO

Safety assessment must be conducted before the commercial release of transgenic silkworms. This study was conducted to assess the potential of transferring transgenic DNA from silkworms to other organisms. One hundred hatched male chickens were evenly assigned into 4 groups (T1-4). Groups T1-3 were fed transgenic silkworms P3+5UI with enhanced green fluorescent protein DNA (EGFP) inserted, A4SOR with superoxide reductase DNA (SOR) inserted, and normal silkworm, respectively. Each chicken was fed one silkworm larva every day for 3 weeks. T4 was the normal feeding control. Twenty chickens were randomly selected from each treatment for sacrifice at 22 days of age. The serum was collected individually for biochemical examination, revealing no difference in the analyzed serum parameters between T4 and T1-3. DNA from the duodenum, jejunum, ileum, liver, kidney, and jejunal digesta was extracted for PCR analysis of EGFP, SOR, silkworm housekeeping gene TIF-4A, and chicken ovalbumin gene. No transgenic DNA or TIF-4A was detected in the digesta and tissues of chickens. The same results were observed in chicken upon increasing the amount and frequency of feeding transgenic silkworms, suggesting that the transgenic DNA from silkworms was degraded in the digestive tract and not transferred into the tissues of chicken. This study revealed that transferr recombinant DNA from transgenic silkworm to another organism is unlikely.

20.
Nano Lett ; 19(11): 8262-8269, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31661618

RESUMO

Understanding the effect of a catalyst on the growth of nanowires is crucial for their controllable synthesis. In this study, we report the growth of InGaP nanowires induced by different-sized Au catalysts by metal-organic chemical vapor deposition. Through electron microscopy characterization, two types of InGaP nanowires are identified, and the difference in catalyst size is shown to cause their different morphological, structural, and compositional characteristics. Furthermore, the influencing mechanism of catalyst size on the formation of hierarchical structures in nanowires is discussed. This study provides an insight for a better understanding of the growth of ternary nanowires, especially the effect of catalyst size, which can be a promising approach to control the ternary nanowire growth, and is therefore beneficial for the design of the corresponding nanowire-based device.

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