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1.
World J Gastrointest Surg ; 16(4): 1165-1175, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690051

RESUMO

BACKGROUND: Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract, often requiring intestinal resection as a common treatment. However, recurrence after surgery is common. The anastomotic configuration after bowel resection appears to be associated with the recurrence of CD. Previous studies have suggested that the Kono-S anastomosis may help to reduce the recurrence rate. However, the results remain controversial. Therefore, evidence-based evidence is needed to prove the advantages of Kono-S anastomosis. AIM: To measure the influence of anastomosis techniques on the long-term relapse rate of CD by conducting a meta-analysis. METHODS: PubMed, Scopus, and Cochrane Library were searched until October 8, 2023. Patients who underwent intestinal resection due to CD were included. The intervention measures included Kono-S anastomosis, whereas the control group received traditional anastomosis such as end-to-end, end-to-side, and side-to-side anastomosis. Only randomized clinical trials and observational studies were included. The primary outcome measures were hospital stay post-surgery, overall postoperative complication incidence, the proportion of Clavien-Dindo grade IIIa or higher, overall postoperative recurrence rate, and Rutgeerts score. RESULTS: From 2011 to 2023, six articles met the inclusion and exclusion criteria. The results indicated that Kono-S anastomosis can reduce the hospital stay post-surgery of patients with CD [MD = -0.26, 95%CI: -0.42 to -0.10, P = 0.002] than other traditional anastomosis methods. Compared to other traditional anastomosis methods, Kono-S anastomosis can significantly reduce the total recurrence rate [MD = 0.40, 95%CI: 0.17 to 0.98, P = 0.05] and postoperative Rutgeerts score [MD = -0.81, 95%CI: -0.96 to -0.66, P < 0.001] in patients with CD. However, there is no significant disparity in the overall occurrence of postoperative complications and the proportion of Clavien-Dindo ≥ IIIa. CONCLUSION: Kono-S anastomosis has the potential to expedite the recuperation of CD and diminish relapse hazards; however, additional larger trials are necessary to authenticate its effectiveness.

2.
ACS Appl Mater Interfaces ; 16(14): 17587-17597, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38547461

RESUMO

Inert atmosphere is normally necessary for fabrication of solid composite electrolytes (SCEs) as a crucial part of solid-state Li-metal batteries in order to avoid undesirable reactions induced by ambient moisture. Herein, we developed an air-processable technique to fabricate SCEs by employing LiCF3SO3 (LiOTf) as the Li salt, which was combined with Li6.4La3Zr1.4Ta0.6O12 (LLZTO) as the fast Li-conductor and polyvinylidene difluoroethylene/polyvinyl acetate (PVDF/PVAC) as the polymer matrix. With the assistance of trace H2O dissolved in electrolyte solution, the room-temperature Li+ conductivity of the obtained aSCE reached as high as 5.09 × 10-4 S cm-1, which was over 3 orders of magnitude higher than that of the one (iSCE, 1.93 × 10-7 S cm-1) cast by the electrolyte solution prepared in an inert atmosphere. The theoretical calculation results reveal that the oxygen atom of H2O exhibits a high propensity to interact with the Li atom in LiOTf (Li···O), thereby establishing a hydrogen bond with the oxygen atom (H···O) in N,N-dimethylformamide (solvent). Such interactions promoted the dissociation of LiOTf and led to the formation of uniform Li+ transportation channels. Simultaneously, the composition distribution was also altered, resulting in a smoother surface of aSCE and lowered crystallinity of PVDF. On this basis, the LiOTf/LLZTO/PVDF/PVAC solution at 60 °C was directly coated onto the surface of the LiFePO4 (LFP) cathode to fabricate the LFP-aSCE film after drying in an oven. The assembled LFP-aSCE/Li battery wetted by trace sulfolane exhibited an initial Coulombic efficiency of 94.7% and a capacity retention rate of up to 96% at 0.2 C (137 mAh g-1) after 180 cycles and a high capacity of 143.7 mAh g-1 at 0.5 C (150 cycles). Overall, this work could pave the way for the facile fabrication of solid electrolytes.

3.
ACS Appl Mater Interfaces ; 15(2): 3037-3046, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36622847

RESUMO

Nanocarbons (NCs) consisting of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) were coated on the surface of nickel foam (NF) via a chemical vapor deposition method. The CNFs formed conductive networks on NF, while the CNTs grew perpendicular to the surface of the CNFs, accompanied with the formation of Ni nanoparticles (Ni NPs) at the end of CNTs. The unique Ni-NCs-coated NF with a porous structure was applied as the three-dimensional (3D) current collector of lithium-sulfur (Li-S) batteries, which provided enough space to accommodate the electrode materials inside itself. Therefore, the 3D interconnected conductive framework of the coated NF collector merged in the electrode materials shortened the path of electron transport, and the generated Ni NPs could adsorb lithium polysulfides (LiPSs) and effectively accelerated the conversion kinetics of LiPSs as well, thereby suppressing the "shuttle effect". Moreover, the rigid framework of NF would also constrain the movement of the electrode compositions, which benefited the stability of the Li-S batteries. As a matter of fact, the Li-S battery based on the Ni-NCs-coated NF collector delivered an initial discharge capacity as high as 1472 mAh g-1 at 0.1C and outstanding high rate capability at 3C (802 mAh g-1). Additionally, low decay rates of 0.067 and 0.08% at 0.2C (300 cycles) and 0.5C (500 cycles) have been obtained, respectively. Overall, our prepared Ni-NCs-coated NF collector is promising for the application in high-performance Li-S batteries.

4.
ChemSusChem ; 15(13): e202102444, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34918485

RESUMO

Currently, low intimacy between hydrogenation sites and acidic sites causes unsatisfactory catalytic activity and selectivity for the synthesis of 2,5-hexanedione from C6 furan aldehydes (5-methylfurfural, 5-hydroxymethylfurfural). Herein, iodine(I) modification of Pd-supported catalysts (such as PdI/Al2 O3 and PdI/SiO2 ) was investigated to modulate the hydrogenation sites and acidic sites. Unlike Pd catalysts that produced 71.4 % yield of 2-hydroxymethyl-5-methyl tetrahydrofuran via an overhydrogenation route of 5-methylfurfural, PdI catalysts showed a high efficiency for 2,5-hexanedione with 93.7 % yield by a hydrogenative ring-opening route. More importantly, the selective synthesis of 2,5-hexanedione from 5-hydroxymethylfurfural with a high yield of 50.2 % by the hydrogenolysis and subsequent ring-opening route was reported for the first time. I-modified Pd nanoparticles produced in-situ hydrogen spillover, which promoted the selective C=O hydrogenation and ring-opening steps by regulating the adsorption configuration of the reactants and the transformation of Lewis to Brønsted acidity, respectively.


Assuntos
Aldeídos , Iodo , Furanos , Hexanonas , Iodetos , Dióxido de Silício
5.
Comput Math Methods Med ; 2021: 4856820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34158819

RESUMO

Thyroid cancer (TC) is the most common endocrine malignant disease with a rising morbidity year by year. Accumulating studies have shown that microRNAs (miRNAs) play a regulatory role in the progression of various tumors, but the molecular regulatory mechanism of miR-196a-2 in TC is still unknown. qRT-PCR was employed to measure the expression of miR-196a-2 and NRXN1 mRNA in TC cells, while western blot was used to detect the protein expression of NRXN1. CCK-8, colony formation and flow cytometry assays were used to measure cell proliferation and apoptosis of TC cells. Dual-luciferase reporter gene assay was used to predict and verify the targeted binding relationship between miR-196a-2 and NRXN1. Our study results manifested that miR-196a-2 was dramatically overexpressed in cells of TC, while NRXN1 was lowly expressed. miR-196a-2 could promote cell proliferation and inhibit cell apoptosis of TC. Additionally, miR-196a-2 could also target and inhibit the expression of NRXN1. Silencing NRXN1 could reverse the inhibitory effect of miR-196a-2 downregulation on cell proliferation of TC, as well as the promoting effect on cell apoptosis. In a conclusion, we found that miR-196a-2 could promote cell proliferation and inhibit cell apoptosis of TC by targeting NRXN1. Therefore, miR-196a-2/NRXN1 is potential to be a molecular therapeutic target for TC.


Assuntos
Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/genética , MicroRNAs/genética , Moléculas de Adesão de Célula Nervosa/antagonistas & inibidores , Moléculas de Adesão de Célula Nervosa/genética , Neoplasias da Glândula Tireoide/genética , Apoptose/genética , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Biologia Computacional , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , MicroRNAs/antagonistas & inibidores , Moléculas de Adesão de Célula Nervosa/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Ensaio Tumoral de Célula-Tronco , Regulação para Cima
6.
J Oncol ; 2021: 8810517, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33542733

RESUMO

OBJECTIVES: Breast cancer is the most common malignant tumor among females, and miRNAs have been reported to play an important regulatory role in breast cancer progression. This study aimed to explore the function and underlying molecular mechanism of miR-301b-3p in breast cancer. METHODS: Differential analysis and survival analysis were performed based on the data accessed from the TCGA-BRCA dataset for identification of the target miRNA. Bioinformatics analysis was conducted to predict the downstream target gene of the miRNA. Real-time quantitative PCR was carried out to detect the expression of miR-301b-3p and nuclear receptor subfamily 3 group C member 2 (NR3C2). Western blot was used to assess the protein expression of NR3C2. Cell counting kit-8 assay was performed to evaluate the proliferation of breast cancer cells. Transwell assay was conducted to determine the migratory and invasive abilities of breast cancer cells. Dual-luciferase reporter assay was employed to verify the targeting relationship between miR-301b-3p and NR3C2. RESULTS: miR-301b-3p was elevated in breast cancer cell lines and promoted cell proliferation, migration, and invasion in terms of its biological function in breast cancer. NR3C2 was validated as a direct target of miR-301b-3p via bioinformatics analysis and dual-luciferase reporter assay, and NR3C2 was downregulated in breast cancer cell lines. The rescue experiment indicated that NR3C2 was involved in the mechanism by which miR-301b-3p regulated the malignant phenotype of breast cancer cells. CONCLUSION: The present study revealed for the first time that miR-301b-3p could foster breast cancer cell proliferation, migration, and invasion by targeting NR3C2, unveiling that miR-301b-3p is a novel carcinogen in breast cancer.

7.
Materials (Basel) ; 12(12)2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31212737

RESUMO

U-shaped graphene domains have been prepared on a copper substrate by chemical vapor deposition (CVD), which can be precisely tuned for the shape of graphene domains by optimizing the growth parameters. The U-shaped graphene is characterized by using scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), and Raman. These show that the U-shaped graphene has a smooth edge, which is beneficial to the seamless stitching of adjacent graphene domains. We also studied the morphology evolution of graphene by varying the flow rate of hydrogen. These findings are more conducive to the study of morphology evolution, nucleation, and growth of graphene domains on the copper substrate.

8.
RSC Adv ; 9(55): 32247-32257, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-35530806

RESUMO

Herein, three-dimensional (3D) N-doped reduced graphene oxide (N-rGO) nanosheets were decorated with a uniform distribution of Co-Ni-S (CNS) nanoparticles to form the CNS/N-rGO composite as a sulfur host material for lithium-sulfur batteries. The CNS nanoparticles and N in CNS/N-rGO strongly interact with polysulfides, whereas graphene, as a conductive network, can improve its electrical conductivity. A CNS/N-rGO/sulfur composite cathode was prepared via the sulfur melting diffusion method. The electrochemical study showed that the CNS/N-rGO/sulfur cathode delivered an initial discharge capacity of 1430 mA h g-1 at a current density of 0.1C. Moreover, it retained a specific capacity of 685 mA h g-1 after 300 cycles at 0.5C with a coulombic efficiency of 98%, which was better than that of commercial rGO. This composite was used as a sulfur cathode for a lithium-sulfur battery, exhibiting excellent rate capability and remarkable performance in terms of long cycling stability.

9.
Nanomaterials (Basel) ; 8(9)2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30205489

RESUMO

3D hybrid nanostructures connecting 1D carbon nanotubes (CNTs) with 2D graphene have attracted more and more attentions due to their excellent chemical, physical and electrical properties. In this study, we firstly report a novel and facile one-step process using template-directed chemical vapor deposition (CVD) to fabricate highly nitrogen doped three-dimensional (3D) N-doped carbon nanotubes/N-doped graphene architecture (N-CNTs/N-graphene). We used nickel foam as substrate, melamine as a single source for both carbon and nitrogen, respectively. The morphology and microstructure were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, isothermal analyses, X-ray photoelectron microscopy and Raman spectra. The obtained 3D N-CNTs/N-graphene exhibits high graphitization, a regular 3D structure and excellent nitrogen doping and good mesoporosity.

10.
Materials (Basel) ; 11(6)2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799439

RESUMO

We report here the synthesis of metal oxide nanosheets (MONs) directly grown on stainless steel substrates by thermal oxidation in the presence of trace amounts of water. The morphology and microstructure of MONs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and atomic force microscopy (AFM). The composition of MONs was determined by the energy dispersive system and X-ray diffraction patterns. The results showed that the as-synthesized MONs were ultrathin, vertically aligned, and mostly transparent. They were polycrystalline and were composed primarily of Cr2O3 and (Fe, Mn)3O4. The optimal condition to synthesize the MONs with an optimal ultra-high surface atom ratio were determined by varying the temperature and time required for the growth of the MONs. It was found that the lateral size of MONs gradually increases as the temperature rises from 1000 to 1100 °C. An optimal temperature of 1100 °C is obtained in terms of the growth density, size and transparency degree growth morphology, and quality. The structure of MONs changes from two-dimensional to three-dimensional networks when the synthesis time is prolonged to more than 1 h.

11.
J Colloid Interface Sci ; 523: 110-120, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29614420

RESUMO

The amino- and phosphorus-codoped (N,P-codoped) porous carbons derived from oil-tea shells were facilely fabricated through a combination of phosphoric acid (H3PO4) activation and amino (polyethylenimine, PEI) modification method. The as-synthesized carbon adsorbents were systematically characterized and evaluated for Cr(VI) removal in aqueous solutions. The relationship between adsorbent properties and adsorption behaviors was illustrated. Moreover, the influences of contact time, initial Cr(VI) concentration, pH, coexisting anions and temperature were also investigated. The adsorption behavior of Cr(VI) could be perfectly described by the pseudo-second-order kinetic model and Sips adsorption model. The maximum adsorption capacity of Cr(VI) on the carbon adsorbents synthesized in this work was 355.0 mg/g, and this excellent Cr(VI) capacity could be sustained with other coexisting anions. In addition to high surface area and suitable pore size distribution, the high Cr(VI) removal capacity is induced by rich heteroatoms incorporation and the Cr(VI) removal mechanism was clearly illustrated. Furthermore, the continuous column breakthrough experiment on obtained N,P-codoped carbon was conducted and well fitted by the Thomas model. This work revealed that PEI modification and P-containing groups could significantly enhance Cr(VI) adsorption capacity and make these N,P-codoped biomass-derived carbons potent adsorbents in practical water treatment applications.

12.
ACS Omega ; 3(6): 7096-7105, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458871

RESUMO

The effects of both graphene nanoplatelets and reduced graphene oxide as additives to the negative active material in valve-regulated lead-acid batteries for electric bikes were investigated. Low-temperature performance, charge acceptance, cycle performance, and water loss were investigated. The test results show that the low-temperature performance, charge acceptance, and large-current discharge performance of the batteries with graphene additives were significantly improved compared to the control battery, and the cycle life under 100% depth of discharge condition was extended by more than 52% from 250 to 380 cycles. Meanwhile, the amount of water loss from the batteries with graphene changed only slightly compared with the control cells. The excellent performance of the batteries can be ascribed to the graphene promoting the negative-plate charge and discharge processes and suppressing the growth of lead sulfate crystals.

13.
RSC Adv ; 8(22): 12157-12164, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35539379

RESUMO

Integration of two-dimensional graphene and one-dimensional carbon nanotubes (CNTs) to create potentially useful 3D mesoscopic carbon structures with enhanced properties relative to the original materials is very desirable. Here, we report a novel and simple route using chemical vapor deposition (CVD) methods to fabricate bead-like nitrogen-doped CNT/graphene composites (NCNT/G) via a simple pyrolysis of the N-rich melamine in the presence of graphene oxide (GO) as a substrate using a Mn-Ni-Co ternary catalyst. We have characterized these structures by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectra, isothermal analyses, and X-ray photoelectron spectroscopy. The three dimensional NCNT/G hybrids have unique network structures, moderate graphitization, high specific surface area, good mesoporosity, and N doping, which makes them promising materials for applications in energy storage and conversion.

14.
Mol Biol Rep ; 40(6): 4065-73, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23292077

RESUMO

The association between a single nucleotide polymorphism rs13281615A > G located in the 8q24 and breast cancer risk is still controversial and ambiguous. Hence, we performed a more convincing and precise estimation of the relationship between 8q24 and breast cancer by meta-analyzing the currently available evidence from literature. PubMed, Ovid, Medline, and Web of Science databases were searched. A total of 10 publications containing 11 studies including 40,762 cases and 50,380 controls were identified. Crude odds ratio with 95 % confidence interval was used to assess the strength of association. We observed that the 8q24 rs13281615A > G polymorphism was significantly correlated with breast cancer risk when all studies were pooled into the meta analysis. In the stratified analysis by ethnicity, significantly increased risks were also found among Caucasians for all genetic models. For mixed ethnicities, significantly increased risks were found for all genetic models except for the allele contrast model. However, no significantly increased risk was found among Africans for all genetic models. Interestingly, when stratified by BRCA1 mutation carriers status, significantly decreased breast cancer risk was found for allele contrast model. But significantly increased breast cancer risk was found in the BRCA2 mutation carriers for all genetic models except for the recessive model. There was no evidence for significant association between 8q24 rs13281615A > G polymorphism and breast cancer risk in BRCA1 and BRCA2 positive cohort in all comparable models. In conclusion, this meta-analysis suggests that the 8q24 rs13281615A > G polymorphism is a low-penetrant risk factor for developing breast cancer but may not be in Africans.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 8/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Feminino , Heterozigoto , Humanos , Modelos Genéticos , Viés de Publicação , Fatores de Risco
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