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1.
Chem Commun (Camb) ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32016195

RESUMO

One-dimensional zig-zag chain and two-dimensional network dysprosium(iii) single-molecule toroics with anisotropy barriers of about 5 and 31 cm-1 under a zero dc field are reported. These are the first one- and two- dimensional homometallic single-molecule toroics reported to date. Furthermore, the two complexes also display white-light emission under UV-light irradiation.

2.
Inorg Chem ; 59(1): 687-694, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820951

RESUMO

The combination of magnetic interaction with high magnetic anisotropy provides a promising way for modulating/fine-tuning molecular magnetic behaviors. Here, we show the building block approach for the synthesis of a family of dilanthanide single-molecule magnets (SMMs) bridged with a cyanometallate starting from a monolanthanide SMM. Contingent on the central para-/diamagnetic [M(CN)6]3- (M = Fe, Co) integrated between two highly anisotropic pentagonal-bipyramid Dy(III) subunits, the remanence of magnetization is OFF/ON below 15 K and they respectively display a record reversal barrier of 659 K among d-f SMMs and 975 K among cyano-bridged SMMs.

3.
Mol Plant ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31838037

RESUMO

The rubber tree, Hevea brasiliensis, produces natural rubber that serves as an essential industrial raw material. Here, we present a high-quality reference genome for a rubber tree cultivar GT1 using single-molecule real-time sequencing (SMRT) and Hi-C technologies to anchor the ∼1.47-Gb genome assembly into 18 pseudochromosomes. The chromosome-based genome analysis enabled us to establish a model of spurge chromosome evolution, since the common paleopolyploid event occurred before the split of Hevea and Manihot. We show recent and rapid bursts of the three Hevea-specific LTR-retrotransposon families during the last 10 million years, leading to the massive expansion by ∼65.88% (∼970 Mbp) of the whole rubber tree genome since the divergence from Manihot. We identify large-scale expansion of genes associated with whole rubber biosynthesis processes, such as basal metabolic processes, ethylene biosynthesis, and the activation of polysaccharide and glycoprotein lectin, which are important properties for latex production. A map of genomic variation between the cultivated and wild rubber trees was obtained, which contains ∼15.7 million high-quality single-nucleotide polymorphisms. We identified hundreds of candidate domestication genes with drastically lowered genomic diversity in the cultivated but not wild rubber trees despite a relatively short domestication history of rubber tree, some of which are involved in rubber biosynthesis. This genome assembly represents key resources for future rubber tree research and breeding, providing novel targets for improving plant biotic and abiotic tolerance and rubber production.

4.
Int J Nanomedicine ; 14: 9483-9496, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819445

RESUMO

Background: The efficacy of radiotherapy for glioma is often limited by the radioresistance of glioma cells. The radiosensitizing effects of silver nanoparticles (AgNPs) on glioma were found in the previous studies of our group. In order to enhance the radiosensitivity of tumor cells and selectively kill them while reducing the side effects of irradiation therapy, targeted modification of AgNPs is urgently needed. Materials and methods: In the present study, AgNPs functionalized with polyethylene glycol (PEG) and aptamer As1411 (AsNPs) were synthesized and subsequently characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. Then the targeting property of AsNPs was evaluated by dark-field imaging, confocal microscopy and in vivo imaging. Both colony formation assay and glioma-bearing mouse model were employed to study the radiosensitizing effect of AsNPs. Results: The characterization results revealed a spherical shape of AgNPs with an average diameter of 18 nm and the successful construction of AsNPs. AsNPs were confirmed to specifically target C6 glioma cells, but not normal human microvascular endothelial cells. Moreover, AsNPs could not only internalize into tumor cells, but also penetrate into the core of tumor spheroids. In vitro experiments showed that AsNPs exhibited a better radiosensitizing effect than AgNPs and PEGylated AgNPs (PNPs), inducing a higher rate of apoptotic cell death. In vivo imaging demonstrated that Cy5-AsNPs preferentially accumulated at the tumor site, and the ratio of fluorescence intensity of Cy5-AsNPs to that of Cy5-PNPs reached the maximum at 6 h post-systemic administration. Furthermore, the combination of AsNPs with irradiation significantly prolonged the median survival time of C6 glioma-bearing mice. Conclusion: Our results indicated that AsNPs could be an effective nano-radiosensitizer for glioma targeting treatment.

5.
Am J Cancer Res ; 9(10): 2140-2155, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31720079

RESUMO

Metabolic syndrome is a significant risk factor for the development of hepatocellular carcinoma (HCC). 25-HC (25-hydroxycholesterol) synthesized from cholesterol plays an important role in lipid metabolism. However, the functions and mechanism of 25-HC in HCC remain largely unknown. In this study, we demonstrated that 25-HC promoted HCC cells migration and intrahepatic and extrahepatic metastasis while did not affect the cells proliferation and apoptosis. Mechanistically, the promotive effect of 25-HC was through up-regulation of Toll-like receptor 4 (TLR4) dependent fatty acid binding protein 4 (FABP4). Inhibition of FABP4 hindered 25-HC-induced cells migration and metastasis. Moreover, up-regulation of FABP4 was observed in HCC tissues from database analysis. In summary, our study reveals the effects and mechanism of 25-HC/TLR4/FABP4 axis in promoting HCC metastasis, which provides novel avenue for therapeutic intervention against HCC progression.

6.
Sci Rep ; 9(1): 17256, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754222

RESUMO

Cancer is a major cause of death worldwide, and an early diagnosis is required for a favorable prognosis. Histological examination is the gold standard for cancer identification; however, large amount of inter-observer variability exists in histological diagnosis. Numerous studies have shown cancer genesis is accompanied by an accumulation of harmful mutations, potentiating the identification of cancer based on genomic information. We have proposed a method, GDL (genome deep learning), to study the relationship between genomic variations and traits based on deep neural networks. We analyzed 6,083 samples' WES (Whole Exon Sequencing) mutations files from 12 cancer types obtained from the TCGA (The Cancer Genome Atlas) and 1,991 healthy samples' WES data from the 1000 Genomes project. We constructed 12 specific models to distinguish between certain type of cancer and healthy tissues, a total-specific model that can identify healthy and cancer tissues, and a mixture model to distinguish between all 12 types of cancer based on GDL. We demonstrate that the accuracy of specific, mixture and total specific model are 97.47%, 70.08% and 94.70% for cancer identification. We developed an efficient method for the identification of cancer based on genomic information that offers a new direction for disease diagnosis.

7.
Am J Cancer Res ; 9(9): 1957-1969, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598397

RESUMO

Tumor associated macrophages (TAMs) in tumor microenvironment can interact with tumor cells and are related to tumor progression. However, the mechanisms that drive the anti-tumor functions of TAMs are not fully understood. The Src homology 2 domain-containing tyrosine phosphatase 2 (Shp2) has been reported to have tumor-suppressing roles in colorectal cancer (CRC). However, a role for Shp2 on TAMs in CRC has not been studied. Here we report that in CRC, Shp2 expression on TAMs is negatively associated with liver metastasis. TAMs require Shp2 for their anti-tumor functions in a cell-cell co-culture system and a mouse model of CRC. Mechanistically, absence of Shp2 on TAMs induces their polarization toward M2 phenotype through the activation of p-STAT3 and inhibition of p-NF-κB p65. The findings of our study imply that Shp2 is a key factor in the tumor microenvironment to facilitate the TAMs' tumor-suppressing functions in colorectal cancer.

8.
Gigascience ; 8(10)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574156

RESUMO

BACKGROUND: The African eggplant (Solanum aethiopicum) is a nutritious traditional vegetable used in many African countries, including Uganda and Nigeria. It is thought to have been domesticated in Africa from its wild relative, Solanum anguivi. S. aethiopicum has been routinely used as a source of disease resistance genes for several Solanaceae crops, including Solanum melongena. A lack of genomic resources has meant that breeding of S. aethiopicum has lagged behind other vegetable crops. RESULTS: We assembled a 1.02-Gb draft genome of S. aethiopicum, which contained predominantly repetitive sequences (78.9%). We annotated 37,681 gene models, including 34,906 protein-coding genes. Expansion of disease resistance genes was observed via 2 rounds of amplification of long terminal repeat retrotransposons, which may have occurred ∼1.25 and 3.5 million years ago, respectively. By resequencing 65 S. aethiopicum and S. anguivi genotypes, 18,614,838 single-nucleotide polymorphisms were identified, of which 34,171 were located within disease resistance genes. Analysis of domestication and demographic history revealed active selection for genes involved in drought tolerance in both "Gilo" and "Shum" groups. A pan-genome of S. aethiopicum was assembled, containing 51,351 protein-coding genes; 7,069 of these genes were missing from the reference genome. CONCLUSIONS: The genome sequence of S. aethiopicum enhances our understanding of its biotic and abiotic resistance. The single-nucleotide polymorphisms identified are immediately available for use by breeders. The information provided here will accelerate selection and breeding of the African eggplant, as well as other crops within the Solanaceae family.

9.
Nat Commun ; 10(1): 4201, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519986

RESUMO

As Charles Darwin anticipated, living fossils provide excellent opportunities to study evolutionary questions related to extinction, competition, and adaptation. Ginkgo (Ginkgo biloba L.) is one of the oldest living plants and a fascinating example of how people have saved a species from extinction and assisted its resurgence. By resequencing 545 genomes of ginkgo trees sampled from 51 populations across the world, we identify three refugia in China and detect multiple cycles of population expansion and reduction along with glacial admixture between relict populations in the southwestern and southern refugia. We demonstrate multiple anthropogenic introductions of ginkgo from eastern China into different continents. Further analyses reveal bioclimatic variables that have affected the geographic distribution of ginkgo and the role of natural selection in ginkgo's adaptation and resilience. These investigations provide insights into the evolutionary history of ginkgo trees and valuable genomic resources for further addressing various questions involving living fossil species.


Assuntos
Evolução Biológica , Genoma de Planta , Ginkgo biloba/genética , Filogenia , Adaptação Fisiológica , China , Fósseis , Genômica , Sementes/genética , Seleção Genética
10.
Bioorg Med Chem ; 27(20): 115049, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466835

RESUMO

Myeloid differentiation protein 2 (MD2) is a co-receptor of toll-like receptor 4 (TLR4) responsible for the recognition of lipopolysaccharide (LPS) and mediates a series of TLR4-dependent inflammatory responses in inflammatory lung diseases including acute lung injury (ALI). Targeting MD2 thus may provide a therapeutic strategy against these lung diseases. In this study, we identified a novel compound 4k with the potent anti-inflammatory activity among 39 methyl gallate derivatives (MGDs). MGD 4k exhibited a high binding affinity to MD2, which in turn prevented the formation of the LPS/MD2/TLR4 complex. In addition, MGD 4k significantly reversed the upregulation of LPS-induced inflammatory mediators such as tumor necrosis factor-α, interleukin-6, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and monocyte chemoattractant protein-1 in vitro and in vivo. Mechanistically, MGD 4k performed anti-inflammatory function by inactivating JNK, ERK and p38 signaling pathways. Taken together, our study identified MGD 4k as a novel potential therapeutic agent for ALI through inhibiting MD2, inflammatory responses, and major inflammation-associated signaling pathways.

11.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366025

RESUMO

In the present work, we developed a simple and rapid sample preparation method for the determination of neonicotinoid pesticides in honey based on the matrix-induced sugaring-out. Since there is a high concentration of sugars in the honey matrix, the honey samples were mixed directly with acetonitrile (ACN)-water mixture to trigger the phase separation. Analytes were extracted into the upper ACN phase without additional phase separation agents and injected into the HPLC system for the analysis. Parameters of this matrix-induced sugaring-out method were systematically investigated. The optimal protocol involves 2 g honey mixed with 4 mL ACN-water mixture (v/v, 60:40). In addition, this simple sample preparation method was compared with two other ACN-water-based homogenous liquid-liquid extraction methods, including salting-out assisted liquid-liquid extraction and subzero-temperature assisted liquid-liquid extraction. The present method was fully validated, the obtained limits of detection (LODs) and limits of quantification (LOQs) were from 21 to 27 and 70 to 90 µg/kg, respectively. Average recoveries at three spiked levels were in the range of 91.49% to 97.73%. Precision expressed as relative standard deviations (RSDs) in the inter-day and intra-day analysis were all lower than 5%. Finally, the developed method was applied for the analysis of eight honey samples, results showed that none of the target neonicotinoid residues were detected.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Mel/análise , Inseticidas/isolamento & purificação , Extração Líquido-Líquido/métodos , Neonicotinoides/isolamento & purificação , Acetonitrilos/química , Cromatografia Líquida de Alta Pressão/normas , Análise de Alimentos , Contaminação de Alimentos , Humanos , Limite de Detecção , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Solventes/química , Água/química
12.
J Pharm Biomed Anal ; 175: 112788, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31382116

RESUMO

During the HPLC related substances testing of pregabalin API, an unknown peak was observed at a level exceeding the identification threshold. Preliminary investigation revealed that this impurity is not a process impurity but rather an artifactual solution degradant or "ghost peak" during the HPLC analysis. By using a strategy that combines LC-PDA/UV-MSn with mechanism-based stress studies, the unknown peak was rapidly identified as a covalent adduct formed between pregabalin and acetonitrile (the latter is a component of the HPLC sample diluent), which is structurally an ethylamidine derivative of pregabalin. It appeared that the formation of this solution degradant was catalyzed by alkaline impurities during the sample preparation. This plausible mechanism was verified by a mechanism-based forced degradation study, in which a base was added into the sample diluent and consequently, the pregabalin-acetonitrile adduct was produced extremely efficiently at a level of ˜92%. Subsequently, the structure of the solution degradant was confirmed as an ethylamidine derivative of pregabalin through characterization by 1D and 2D NMR; the formation of the ethylamidine moiety is apparently via a nucleophilic attack on the cyano group of acetonitrile by the amino group of pregabalin. Due to the extensive presence of primary and secondary amine moieties in drug substances, this kind of artifactual solution degradation would likely occur during the sample preparations of these amine drugs in their HPLC analyses. In a GMP environment, such an event would trigger undesirable out-of-specification (OOS) investigations. The results of this study should help resolve such OOS investigations or prevent their happening from the very beginning. Furthermore, the somewhat surprising finding of the rather facile reaction that produces the ethylamidine moiety using simple alkylnitrile reagents, such as acetonitrile, may be of practical value in the synthesis of alkylamidines.


Assuntos
Acetonitrilos/química , Pregabalina/química , Soluções/química , Aminas/química , Catálise , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Excipientes/química , Espectroscopia de Ressonância Magnética/métodos
13.
Microorganisms ; 7(6)2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31212635

RESUMO

Trans-splicing mechanisms have been documented in many lineages that are widely distributed phylogenetically, including dinoflagellates. The spliced leader (SL) sequence itself is conserved in dinoflagellates, although its gene sequences and arrangements have diversified within or across different species. In this study, we present 18 Fugacium kawagutii SL genes identified from stranded RNA-seq reads. These genes typically have a single SL but can contain several partial SLs with lengths ranging from 103 to 292 bp. Unexpectedly, we find the SL gene transcripts contain sequences upstream of the canonical SL, suggesting that generation of mature transcripts will require additional modifications following trans-splicing. We have also identified 13 SL-like genes whose expression levels and length are comparable to Dino-SL genes. Lastly, introns in these genes were identified and a new site for Sm-protein binding was proposed. Overall, this study provides a strategy for fast identification of SL genes and identifies new sequences of F. kawagutii SL genes to supplement our understanding of trans-splicing.

14.
Inorg Chem ; 58(9): 5914-5921, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31009212

RESUMO

Four isostructural dinuclear lanthanide complexes based on 4-azotriazolyl-3-hydroxy-2-naphthoic acid (H3ATNA) and 3-hydroxy-2-naphthoic acid (H2NA) ligands, {[Ln2(HATNA)2(HNA)2(H2O)4]·6DMF} (Ln = Dy (1), Tb (2), Sm (3), Eu (4); DMF = N, N-dimethylformamide) have been prepared and characterized by X-ray diffraction crystallography, dc/ac magnetic characterization, and fluorescent spectrometry. The crystallographic data reveal dinuclear lanthanide cores of complexes 1-4, bridged by phenoxo and µ1,3 carboxyl groups. Each nine-coordinated Ln(III) ion is located in a slightly distorted monocapped square antiprism. The ligand of H3ATNA displays a unique antenna effect in complex 4. Complexes 1-3 display only two ligand-centered fluorescent emissive peaks around 450 and 600 nm, and complex 4 shows four characteristic Eu(III)-centered emission bands at 593, 618, 653, and 698 nm under excitation at 348 nm. Complex 1 exhibits single-molecule magnet behavior that is rationalized through ab initio calculations.

15.
Biochem Biophys Res Commun ; 514(1): 231-238, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31029422

RESUMO

This study focuses on the role of miR-7 in colorectal cancer (CRC) cells by targeting thyroid receptor interactor protein 6 (TRIP6). Here, we report that miR-7 expression was down-regulated in colorectal cancer tissues and cell lines due to DNA hypermethylation. miR-7 overexpression significantly inhibits the proliferation and migration of CRC cells in vitro. TRIP6 was found to be a direct target gene of miR-7. The proliferation inhibition of CRC cells mediated by miR-7 could be rescued after TRIP6 overexpression in vitro and in vivo. Moreover, overexpression of TRIP6 reduced miR-7 inhibitor-mediated CRC cell migration and invasion. These findings demonstrate that miR-7 could inhibit the proliferation and migration of CRC cells by targeting TRIP6 and that miR-7 might serve as a good strategy for diagnosing and treating CRC.

16.
J Exp Med ; 216(5): 1182-1198, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30940720

RESUMO

Subclinical hypothyroidism is associated with cardiovascular diseases, yet the underlying mechanism remains largely unknown. Herein, in a common population (n = 1,103), TSH level was found to be independently correlated with both carotid plaque prevalence and intima-media thickness. Consistently, TSH receptor ablation in ApoE -/- mice attenuated atherogenesis, accompanied by decreased vascular inflammation and macrophage burden in atherosclerotic plaques. These results were also observed in myeloid-specific Tshr-deficient ApoE -/- mice, which indicated macrophages to be a critical target of the proinflammatory and atherogenic effects of TSH. In vitro experiments further revealed that TSH activated MAPKs (ERK1/2, p38α, and JNK) and IκB/p65 pathways in macrophages and increased inflammatory cytokine production and their recruitment of monocytes. Thus, the present study has elucidated the new mechanisms by which TSH, as an independent risk factor of atherosclerosis, aggravates vascular inflammation and contributes to atherogenesis.

17.
Soft Robot ; 6(4): 495-506, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30907704

RESUMO

Soft robots exhibit many exciting properties due to their softness and body compliance. However, to interact with the environment safely and to perform a task effectively, a soft robot faces a series of challenges such as dexterous motion, proprioceptive sensing, and robust control of its deformable bodies. To address these issues, this article presents a method for fabrication and dynamic modeling of a novel bidirectional bending soft pneumatic actuator that embeds a curvature proprioceptive sensor. The bidirectional bending deformation was generated by two similar chambers with a sinusoidal shape for reducing the internal dampness during bending deformation. An optical waveguide made from flexible poly (methyl methacrylate) material that is immune to the inlet pressure was embedded into the actuator body to measure its bending angle. A dynamic modeling framework based on step response and parameter fitting was proposed to establish a simple differential equation that can describe the nonlinear behavior of the soft actuator. Hence, a sliding mode controller is designed based on this differential equation and the Taylor expansion. The proposed dynamical model and the sliding mode controller were validated by trajectory tracking experiments. The performance of the bidirectional bending soft actuator, such as the linear output of the curvature sensor in different inflating patterns, the proprioceptive sensitiveness to the external environment, the output force, and large bending range under relatively small pressure, was evaluated by relevant experimental paradigms. Prototypes from the novel design and fabrication process demonstrated the soft actuator's potential applications in industrial grasping and hand rehabilitation.

18.
BMJ Open ; 9(1): e017637, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30700474

RESUMO

INTRODUCTION: Adjuvant chemotherapy with the CapeOX regimen is now widely used for treating colorectal cancer. However, prior studies have demonstrated better efficacy of pre-operative/neoadjuvant chemotherapy without increase of safety risks. METHODS AND ANALYSIS: This multicentre, open-label, parallel-group, randomised, controlled, phase III study aims to compare the efficacy and safety of perioperative CapeOX chemotherapy with the postoperative one for treating patients with locally advanced R0 resectable colon cancers in China. In total 1370 eligible patients will be randomised to: the test group, up to four cycles (every 3 weeks is a cycle, Q3W) of chemotherapy plus radical surgery plus up to four cycles of post-operative chemotherapy; or the control group, radical surgery first, then up to eight cycles of chemotherapy. In each cycle, oxaliplatin will be given at a dose of 130 mg/m2 through continuous IV infusion for 2 hours on the first day. From day 1 to day 14, capecitabine will be taken orally every morning and evening at a dose of 1000mg/m2/d. The primary outcome measure is the 3-year disease free survival. The objective response rate, R0 resection rate, overall survival, as well as the adverse events will also be measured as second endpoints. The study may include two periods. If results of period 1 are not favourable, period 2 will be initiated, recruiting genetically sensitive patients and repeating the same process with period 1. ETHICS AND DISSEMINATION: Informed consent will be required from, and provided, by all subjects. The study protocol has been approved by the independent ethics committee of Shanghai Fudan University Cancer Centre. This study will clearly demonstrate the potential benefit of perioperative chemotherapy with the CapeOX regimen. Results will be shared among all the participating centres, and with policymakers and the academic community to promote the clinical management of colon cancer. TRIAL REGISTRATION NUMBER: NCT03125980.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , Neoplasias do Colo/terapia , Terapia Neoadjuvante/métodos , Capecitabina/uso terapêutico , Quimioterapia Adjuvante , China , Ensaios Clínicos Fase III como Assunto , Neoplasias do Colo/mortalidade , Neoplasias do Colo/cirurgia , Relação Dose-Resposta a Droga , Humanos , Estudos Multicêntricos como Assunto , Estadiamento de Neoplasias , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina/uso terapêutico , Cuidados Pré-Operatórios/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida
19.
PeerJ ; 7: e6350, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30792941

RESUMO

Objective: This study was performed to identify a reasonable cutoff age for defining older patients with colorectal cancer (CRC) and to examine whether old age was related with increased colorectal cancer-specific death (CSD) and poor colorectal cancer-specific survival (CSS). Methods: A total of 76,858 eligible patients from the surveillance, epidemiology, and end results (SEER) database were included in this study. The Cox proportional hazard regression model and the Chow test were used to determine a suitable cutoff age for defining the older group. Furthermore, a propensity score matching analysis was performed to adjust for heterogeneity between groups. A competing risk regression model was used to explore the impact of age on CSD and non-colorectal cancer-specific death (non-CSD). Kaplan-Meier survival curves were plotted to compare CSS between groups. Also, a Cox regression model was used to validate the results. External validation was performed on data from 1998 to 2003 retrieved from the SEER database. Results: Based on a cutoff age of 70 years, the examined cohort of patients was classified into a younger group (n = 51,915, <70 years of old) and an older group (n = 24,943, ≥70 years of old). Compared with younger patients, older patients were more likely to have fewer lymph nodes sampled and were less likely to receive chemotherapy and radiotherapy. When adjusted for other covariates, age-dependent differences of 5-year CSD and 5-year non-CSD were significant in the younger and older groups (15.84% and 22.42%, P < 0.001; 5.21% and 14.21%, P < 0.001). Also an age of ≥70 years remained associated with worse CSS comparing with younger group (subdistribution hazard ratio, 1.51 95% confidence interval (CI) [1.45-1.57], P < 0.001). The Cox regression model as a sensitivity analysis had a similar result. External validation also supported an age of 70 years as a suitable cutoff, and this older group was associated with having reduced CSS and increased CSD. Conclusions: A total of 70 is a suitable cutoff age to define those considered as having elderly CRC. Elderly CRC was associated with not only increased non-CSD but also with increased CSD. Further research is needed to provide evidence of whether cases of elderly CRC should receive stronger treatment if possible.

20.
Dalton Trans ; 48(10): 3467-3475, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30793718

RESUMO

Four 3-(tetrazol-5-yl)-5-(pyrid-2-yl)-1,2,4-triazole (H2TPT) based complexes of [Co2(TPT)2(H2O)2] (1), [Mn2(TPT)2(H2O)2] (2), [Mn(TPT)(H2O)2]n (3) and [Cu(TPT)]n (4) have been solvothermally synthesized and structurally characterized by X-ray single-crystal diffraction analysis. Complexes 1 and 2 display isostructural dinuclear structures, while complex 3 exhibits a 1D zigzag chain structure. The structural difference for 2 and 3 may be caused by 100 and 160 °C temperature-controlled conditions. Complex 4 is a 3D framework structure in which the Cu2+ ion is in square pyramid coordination geometry. Complexes 1-4 display good thermal stability evaluated by thermogravimetric analysis. Complexes 1 and 4 show very strong antiferromagnetic interactions. The electrocatalytic oxygen evolution of complexes 1-4 was tested under neutral conditions, which revealed that the four complexes possess electrocatalytic oxygen evolution activity. Complex 1 exhibits a current density of 10.0 mA cm-2 at a potential of 2.00 V (vs. RHE), presenting 50-fold improvement in specific activity over the glassy carbon electrode.

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