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1.
J Am Chem Soc ; 146(1): 1042-1052, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147589

RESUMO

Electrocatalytic coupling of CO and N2 to synthesize urea under ambient conditions is considered a promising strategy to replace traditional industrial technology. It is crucial to find efficient electrocatalysts that can adsorb and activate N2 and promote the C-N coupling reaction. Herein, a new two-dimensional porous carbon nitride material with multiactive sites is designed, in which boron and transition metal are embedded. Through a series of screening, B2Cr2, B2Mn2, and B2Os2 are predicted to be potential electrocatalysts for urea synthesis. Mechanistic studies are performed on bidentate metal-metal and metal-boron sites, and both NCON and CO mechanisms are explored. The electronic structure analysis shows that there is a strong N2 chemical adsorption within the bidentate site and that the N≡N bond is significantly activated. A new mechanism where free CO is inserted for C-N coupling within the two-dimensional porous structure is proposed.

2.
Dis Colon Rectum ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773832

RESUMO

BACKGROUND: There is concern regarding the possibility of postoperative complications for laparoscopic right colectomy. OBJECTIVE: To evaluate the risk factors of postoperative complications for patients undergoing laparoscopic right colectomy. DESIGN: This was an observational study. SETTINGS: This was a post-hoc analysis of a prospective, multicenter, randomized controlled trial (RELARC trial, NCT02619942). PATIENTS: Patients included in the modified intention-to-treat analysis in RELARC trial were all enrolled in this study. MAIN OUTCOME MEASURES: Risk factors for postoperative complications were identified using univariate and multivariable logistic regression analysis. RESULTS: Of 995 patients, 206 (20.7%) had postoperative complications. Comorbidity (p = 0.02, OR: 1.544, 95% CI: 1.077-2.212) and operative time >180 min (p = 0.03, OR: 1.453, 95% CI: 1.032-2.044) were independent risk factors for postoperative complications. While female (p = 0.04, OR: 0.704, 95% CI: 0.506-0.980) and extracorporeal anastomosis (p < 0.001, OR: 0.251, 95% CI: 0.166-0.378) were protective factors. Eighty (8.0%) had overall surgical site infection, 53 (5.3%) had incisional SSI, and 33 (3.3%) had organ/space SSI. Side-to-side anastomosis was a risk factor for overall surgical site infection (p < 0.001, OR: 1.912, 95% CI: 1.118-3.268) and organ/space surgical site infection (p = 0.005, OR: 3.579, 95% CI: 1.455-8.805). Extracorporeal anastomosis was associated with a reduced risk of overall surgical site infection (p < 0.001, OR: 0.239, 95% CI: 0.138-0.413), organ/space surgical site infection (p = 0.002 OR: 0.296, 95% CI: 0.136-0.646), and incisional surgical site infection (p < 0.001, OR: 0.179, 95% CI: 0.099-0.322). Diabetes (p = 0.039 OR: 2.090, 95% CI: 1.039-4.205) and conversion to open surgery (p = 0.013 OR: 5.403, 95% CI: 1.437-20.319) were risk factors for incisional surgical site infection. LIMITATIONS: Due to the retrospective nature, the key limitation is the lack of prospective documentation and standardization about perioperative management of these patients such as preoperative optimization, bowel prep regimes and antibiotic regimes, which may be confounder factors of complications. All surgeries were done by experienced surgeons and the patients enrolled were relatively young, generally healthy, and non-obese. It is unclear whether the results will be generalizable to obese and other populations worldwide. CONCLUSIONS: Male, comorbidity, prolonged operative time, and intracorporeal anastomosis were independent risk factors of postoperative complications of laparoscopic right colectomy. Side-to-side anastomosis was associated with an increased risk of organ/space surgical site infection. Extracorporeal anastomosis could reduce the incidence of overall surgical site infection. Diabetes and conversion to open surgery were associated with an increased risk of incisional surgical site infection. See Video Abstract.

3.
Surg Endosc ; 38(4): 1867-1876, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307959

RESUMO

BACKGROUND: The KangDuo surgical robot (KD-SR-01) was recently developed in China. This study aims to evaluate the short-term outcomes of KD-SR-01 for colorectal cancer surgery. METHODS: This is a multicentre randomised controlled noninferiority trial conducted in three centers in China. Enrolled patients were randomly assigned at a 1:1 ratio to receive surgery using the KD-SR-01 system (KD group) or the da Vinci Xi (DV) robotic system (DV group). The primary endpoint was the success rate of operation. The second endpoints were surgical outcomes, pathological outcomes, and postoperative outcomes. RESULTS: Between July 2022 and May 2023. A total of 100 patients were included in the trial and randomly assigned to the KD group (50 patients) and the DV group (50 patients). All cases were completed successfully without conversion to laparoscopic surgery. The time to flatus and the incidence of postoperative complications of Clavien-Dindo grade II or higher grade were comparable between the two groups. Surgeons reported a high level of comfort with the KD-SR-01 system. In the subgroup analysis of different operative procedures, there were no significant differences in docking time, console time, blood loss, and the length of the incision for extraction between the two groups. There were no differences in pathological outcomes including maximum tumor diameter, circumferential resection margin, distal resection margin, and number of harvested lymph nodes. CONCLUSIONS: The KD-SR-01 system was a viable option for colorectal cancer robotic surgery, with acceptable short-term outcomes comparable to the da Vinci Xi robotic system.


Assuntos
Neoplasias Colorretais , Procedimentos Cirúrgicos do Sistema Digestório , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Margens de Excisão , Laparoscopia/métodos , Neoplasias Colorretais/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
4.
J Am Chem Soc ; 145(12): 7030-7039, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921233

RESUMO

The development of efficient and stable catalysts for the electrocatalytic CO2 and CO reduction reactions (CORR) is under active investigation, but the problems of poor selectivity and low efficiency for C2 products still exist. We design a two-dimensional carbon nitride material (C5N2H2) that contains an eight N-atom structure capable of coordinating four-metal atom clusters and supporting simultaneously two carbon oxide molecules needed for the C2 coupling. The designed material has excellent electrical conductivity and stability. After high-throughput screening of catalytic performance of multiple four-metal clusters embedded into the framework, we systematically investigate the CORR process of 11 candidates. We find that Cu4-C5N2H2 has superior selectivity and low limiting potential for generating ethylene, while Cu2Zn2-C5N2H2 is selective and efficient to synthesize ethanol. Further, we discover a novel type of descriptor related to 2D material flexibility to evaluate the potential-determining step for generating ethylene. Our report both broadens the possibilities for few-atom CO reduction and demonstrates a novel substrate flexibility-related descriptor to predict the catalytic performance of materials.

5.
BMC Cancer ; 23(1): 797, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37718392

RESUMO

BACKGROUND: We aimed to analyze the benefit of adjuvant chemotherapy in high-risk stage II colon cancer patients and the impact of high-risk factors on the prognostic effect of adjuvant chemotherapy. METHODS: This study is a multi-center, retrospective study, A total of 931 patients with stage II colon cancer who underwent curative surgery in 8 tertiary hospitals in China between 2016 and 2017 were enrolled in the study. Cox proportional hazard model was used to assess the risk factors of disease-free survival (DFS) and overall survival (OS) and to test the multiplicative interaction of pathological factors and adjuvant chemotherapy (ACT). The additive interaction was presented using the relative excess risk due to interaction (RERI). The Subpopulation Treatment Effect Pattern Plot (STEPP) was utilized to assess the interaction of continuous variables on the ACT effect. RESULTS: A total of 931 stage II colon cancer patients were enrolled in this study, the median age was 63 years old (interquartile range: 54-72 years) and 565 (60.7%) patients were male. Younger patients (median age, 58 years vs 65 years; P < 0.001) and patients with the following high-risk features, such as T4 tumors (30.8% vs 7.8%; P < 0.001), grade 3 lesions (36.0% vs 22.7%; P < 0.001), lymphovascular invasion (22.1% vs 6.8%; P < 0.001) and perineural invasion (19.4% vs 13.6%; P = 0.031) were more likely to receive ACT. Patients with perineural invasion showed a worse OS and marginally worse DFS (hazardous ratio [HR] 2.166, 95% confidence interval [CI] 1.282-3.660, P = 0.004; HR 1.583, 95% CI 0.985-2.545, P = 0.058, respectively). Computing the interaction on a multiplicative and additive scale revealed that there was a significant interaction between PNI and ACT in terms of DFS (HR for multiplicative interaction 0.196, p = 0.038; RERI, -1.996; 95%CI, -3.600 to -0.392) and OS (HR for multiplicative interaction 0.112, p = 0.042; RERI, -2.842; 95%CI, -4.959 to -0.725). CONCLUSIONS: Perineural invasion had prognostic value, and it could also influence the effect of ACT after curative surgery. However, other high-risk features showed no implication of efficacy for ACT in our study. TRIAL REGISTRATION: This study is registered on ClinicalTrials.gov, NCT03794193 (04/01/2019).


Assuntos
Neoplasias do Colo , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/cirurgia , Fatores de Risco , Interpretação Estatística de Dados , Quimioterapia Adjuvante
6.
J Immunol ; 207(4): 1099-1111, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34312258

RESUMO

Understanding the function of SARS-CoV-2 Ag-specific T cells is crucial for the monitoring of antiviral immunity and vaccine design. Currently, both impaired and robust T cell immunity is described in COVID-19 patients. In this study, we explored and compared the effector functions of SARS-CoV-2-reactive T cells expressing coinhibitory receptors and examine the immunogenicity of SARS-CoV-2 S, M, and N peptide pools in regard to specific effector T cell responses, Th1/Th2/Th17, in COVID-19 patients. Analyzing a cohort of 108 COVID-19 patients with mild, moderate, and severe disease, we observed that coinhibitory receptors (e.g., PD-1, CTLA-4, TIM-3, VISTA, CD39, CD160, 2B4, TIGIT, Gal-9, and NKG2A) were upregulated on both CD4+ and CD8+ T cells. Importantly, the expression of coinhibitory receptors on T cells recognizing SARS-CoV-2 peptide pools (M/N/S) was associated with increased frequencies of cytokine-producing T cells. Thus, our data refute the concept of pathological T cell exhaustion in COVID-19 patients. Despite interindividual variations in the T cell response to viral peptide pools, a Th2 phenotype was associated with asymptomatic and milder disease, whereas a robust Th17 was associated with severe disease, which may potentiate the hyperinflammatory response in patients admitted to the Intensive Care Unit. Our data demonstrate that T cells may either play a protective or detrimental role in COVID-19 patients. This finding could have important implications for immune correlates of protection, diagnostic, and prophylaxis with respect to COVID-19 management.


Assuntos
COVID-19/imunologia , SARS-CoV-2/imunologia , Células Th17/imunologia , Células Th2/imunologia , Adulto , Idoso , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Proteínas da Matriz Viral/imunologia
7.
Surg Endosc ; 37(8): 6208-6219, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37170026

RESUMO

BACKGROUND: Intracorporeal anastomosis (IA) is associated with reduced surgical site infection (SSI) and other postoperative complications in laparoscopic right colectomy (LRC). However, evidence is inadequate for IA in laparoscopic left colectomy (LLC). This study aimed to determine the effect of IA and extracorporeal anastomosis (EA) on SSI and other short-term postoperative complications in LLC. METHODS: In this retrospective multicenter propensity score-matched (PSM) cohort study, we enrolled consecutive patients who underwent LLC with IA (TLLC/IA) and laparoscopic-assisted left colectomy with EA (LALC/EA) at two medical centers between January 2015 and September 2021. Propensity score matching with a 1:2 ratio was employed. The primary outcome was SSI occurrence. Secondary outcomes were operating time, intraoperative hemorrhage, other postoperative complications, and pathological outcomes. RESULTS: Overall, 574 and 99 patients received LALC/EA and TLLC/IA, respectively. After PSM, 84 patients with TLLC/IA were matched with 141 patients with LALC/EA. Thirty patients (13.3%) patients experienced SSI (17.0% in LALC/EA vs 7.1% in TLLC/IA). IA was associated with a reduced risk of overall SSI and superficial/deep SSI compared with EA after PSM, with OR of 0.375 (95% CI, 0.147-0.959, P = 0.041). and 0.148 (95% CI, 0.034-0.648, P = 0.011), respectively. Multivariate analysis of unmatched patients indicated similar results. In the analysis of secondary outcomes, LALC/EA may have a shorter operating time (absolute mean difference - 13.41 [95% CI, - 23.76 to - 3.06], P = 0.002) and a higher risk of intraoperative hemorrhage (absolute risk difference 4.96 [95% CI, - 0.09 to 9.89], P = 0.048). CONCLUSIONS: IA in LLC is associated with a reduced risk of overall SSI and superficial/deep SSI. However, it may require a longer operating time.


Assuntos
Neoplasias do Colo , Laparoscopia , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Estudos de Coortes , Pontuação de Propensão , Estudos Retrospectivos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Neoplasias do Colo/cirurgia , Colectomia/efeitos adversos , Colectomia/métodos , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Perda Sanguínea Cirúrgica , Resultado do Tratamento
8.
World J Surg ; 47(3): 785-795, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36635607

RESUMO

BACKGROUND: Current studies did not draw definitive conclusions on comparison of intracorporeal anastomosis (ICA) with extracorporeal anastomosis (ECA) in laparoscopic right colectomy. Whether the intraperitoneal contamination induced by ICA can result in higher risk of postoperative abdominal infection remains unclear. This study was aimed to compare the short-term outcomes, especially the risk of abdominal infection after ICA versus ECA. METHODS: This was an observational cohort study as a secondary analysis of a randomized controlled trial (RCT)-RELARC trial (NCT02619942). The patients enrolled in the RELARC trial were diagnosed with primary colon adenocarcinoma without distant metastasis and underwent radical laparoscopic right colectomy between Jan 2016 and Dec 2019. In our study the patients who converted to open surgery in RELARC trial were excluded. The short-term outcomes were compared between ICA and ECA. The primary endpoint was abdominal infection. The inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) was used for adjusting the potential confounders. RESULTS: This study enrolled 975 patients with 119 patients undergoing ICA and 856 patients undergoing ECA. The incidence of abdominal infection was higher in ICA group (9.2% versus 1.5%, RR from IPTW = 5.7 (95%CI: 2.6-12.6), P < 0.001) as well as the incidence of wound infection (14.3% vs 3.3%, RR from IPTW = 5.0 (95%CI: 2.9-8.6), P < 0.001). ICA was associated with higher incidence of Clavien-Dindo (CD) grade I and II complications (CD-I: 15.1% versus 6.8%, RR from IPTW = 2.4 (95%CI: 1.5-3.9), P < 0.001; CD-II: 26.9% versus 8.2%, RR from IPTW = 3.6 (95%CI: 2.5-5.1), P < 0.001) but similar incidence of CD-III ~ IV complications compared to ECA (3.4% vs 2.1%, RR from IPTW = 1.2 (95%CI: 0.4-4.0), P = 0.73). In ICA group, choosing another incision rather than lengthening main port site decreased the incidence of wound infection although without statistical significance (17.3% (14/81) versus 7.9% (3/38), crude RR = 2.2 (95%CI: 0.7-7.2), P = 0.17). CONCLUSION: ICA is likely to be associated with higher risk of abdominal infection and CD-I ~ II complications.


Assuntos
Neoplasias do Colo , Infecções Intra-Abdominais , Laparoscopia , Infecção dos Ferimentos , Humanos , Laparoscopia/efeitos adversos , Anastomose Cirúrgica/efeitos adversos , Colectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos de Coortes , Infecções Intra-Abdominais/cirurgia , Resultado do Tratamento , Neoplasias do Colo/cirurgia , Neoplasias do Colo/complicações , Estudos Retrospectivos
9.
Mol Reprod Dev ; 89(9): 413-422, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35853138

RESUMO

In this study, we investigated the mitochondrial energy supply capacity and molecular mechanisms of apoptosis, mitochondrial fission, and mitophagy in regulating mitochondrial degeneration in testis of striped dwarf hamsters (Cricetulus barabensis) under mild low temperature (15°C) and short daylight (10 h:14 h) conditions. Results showed that under moderate daylight and mild low temperature (ML), short daylight and moderate temperature (SM), short daylight and mild low temperature (SL) conditions, the mitochondria were swollen and cristae were disrupted. Compared with the moderate daylight & moderate temperature group (MM; 12 h:12 h, 22°C), the number of mitochondria was significantly decreased in the SM and SL groups. Both short daylight and mild low temperature reduced the protein expression of citrate synthase, thus the energy supply capacity of mitochondria may be weakened. Compared with the MM group, bax/bcl2 protein expression was higher in three treatment groups, and caspase3 activity increased in SM and SL groups, suggesting that short daylight can induce apoptosis. DRP1 protein expression showed no difference in four groups, while the FIS1 protein expression was significantly decreased in three treatment groups, this indicates that short daylight and mild low temperature can increase mitochondrial fission level. PINK1 protein expression was significantly increased in ML and SL groups, indicates that mild low temperature will lead to increased mitophagy level. Generally, short daylight induced degeneration of mitochondria in the testis of hamsters mainly by increasing apoptosis, while under mild low temperature, balanced regulation of mitophagy and mitochondrial fission appear to contribute to the protection of mitochondria.


Assuntos
Mitocôndrias , Testículo , Animais , Citrato (si)-Sintase/metabolismo , Citrato (si)-Sintase/farmacologia , Cricetinae , Cricetulus , Masculino , Mitocôndrias/metabolismo , Proteínas Quinases/metabolismo , Proteínas Quinases/farmacologia , Temperatura , Testículo/metabolismo , Proteína X Associada a bcl-2/metabolismo
10.
Analyst ; 147(9): 1873-1880, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35420086

RESUMO

Early diagnosis of tumor markers is of great importance for the successful treatment of cancer. As a high-throughput and high-sensitivity detection technology, liquid suspension biochips based on quantum dot (QD) encoded microspheres have been widely used in the immunodetection of tumor markers. In this work, maleic anhydride grafted PLA (PLA-MA) microspheres based on quantum dot encoding were used as carriers for liquid phase suspension biochips for the immunoassay of tumor markers. PLA-MA fluorescent beads are prepared by embedding CdSe/ZnS quantum dots in PLA-MA using Shirasu porous glass (SPG) membrane emulsification technology, which has high fluorescence intensity, good stability, and good dispersion. Fluorescent immunoassays on dipsticks found that PLA-MA microspheres have high biological activity and good stability, which is conducive to immunoassays. Based on this, using the characteristics of CdSe/ZnS quantum dots and flow cytometry, monochromatic and two-color coding methods were developed, and 9 distinguishable coding beads were prepared. The results showed that PLA-MA fluorescent microspheres exhibited good biocompatibility, stable coding signals, low background noise, and low detection limits when performing quaternary immunoassays on tumor markers CA125, CA199, CA724, and CEA by CdSe/ZnS QD-encoded PLA-MA microsphere binding flow cytometry.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Compostos de Selênio , Biomarcadores Tumorais , Corantes , Imunoensaio/métodos , Anidridos Maleicos , Microesferas , Poliésteres , Sulfetos , Compostos de Zinco
11.
J Immunol ; 204(9): 2474-2491, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32205423

RESUMO

We report significant upregulation of Galectin-9 (Gal-9) and VISTA on both CD4+ and CD8+ T cells in HIV-infected human patients. Gal-9 and VISTA expression was associated with impaired T cells effector functions. Although Gal-9 was coexpressed with other coinhibitory receptors such as TIGIT, CD160, CD39, and VISTA, it was simultaneously coexpressed with PD-1. Coexpression of Gal-9 with PD-1 was associated with a more terminally exhausted T cell phenotype in HIV-1 patients. This was marked by higher expression of EOMES, blimp1, and Glut1 in Gal-9+ versus Gal-9- T cells, which is consistent with an exhausted T cell phenotype. Gal-9+ T cells exhibited the phenotype characteristics of effector T cells (CD45RA+, CD45RO-/lo, CD62L-, CD27lo) with higher T-bet expression. A positive correlation between the plasma viral load with the plasma Gal-9 levels in treatment-naive HIV patients and an inverse correlation between CD4 count with the frequency of CD4+Gal-9+ T cells were observed. Increased percentages of Gal-9+ T cells was evident in HIV-treated patients. Enhanced expression of Gal-9 on T cells following PMA stimulation via protein kinase C suggests persistent TCR stimulation as a potential contributing factor in Gal-9 upregulation in HIV patients. This was supported by the constant degranulation of Gal-9+ T cells. Moreover, CD44 clustering by Gal-9 may influence cytoskeleton rearrangement and coclustering of CD3, which likely impact initiation of signal transduction via TCR. Our preliminary data also confirm upregulation of Gal-9 on T cells in hepatitis B virus and HPV infections. These results demonstrate a novel role for Gal-9 and VISTA in HIV pathogenesis.


Assuntos
Antígenos B7/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Galectinas/metabolismo , Infecções por HIV/metabolismo , Complexo CD3/imunologia , Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/patogenicidade , Humanos , Receptores de Hialuronatos/imunologia , Receptores de Hialuronatos/metabolismo , Proteína Quinase C/imunologia , Proteína Quinase C/metabolismo , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Regulação para Cima/imunologia , Carga Viral/imunologia
12.
Macromol Rapid Commun ; 43(17): e2200157, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35503683

RESUMO

For double network (DN) hydrogels, their performance can be tuned by adjusting the interaction between their two networks. A novel DN hydrogel toughening approach is proposed by employing Janus nanoparticles (JNs) as crosslinkers to gain a conjoined-network hydrogel. First, a kind of JNs modified by amino groups and quaternary ammonium salt is synthesized, named R3 N+ -JN-NH2 . The DN hydrogel is fabricated based on ionic coordination between calcium chloride (CaCl2 ) and sodium alginate (Alg), as well as covalent (benzoic imine) between glycol chitosan (GC) and benzaldehyde-capped poly(ethylene oxide) (BzCHO-PEO-BzCHO). Based on the same covalent and ionic dynamic crosslinking mechanism, the added R3 N+ -JN-NH2 interacts with two networks to promote crosslinking to form a dually crosslinked structure. The R3 N+ -JN-NH2 effectively provides more energy dissipation, and the hydrogel with conjoined networks shows better compression resistance.


Assuntos
Hidrogéis , Nanopartículas Multifuncionais , Alginatos/química , Hidrogéis/química , Polietilenoglicóis/química
13.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296584

RESUMO

Graphite anodes are well established for commercial use in lithium-ion battery systems. However, the limited capacity of graphite limits the further development of lithium-ion batteries. Hard carbon obtained from biomass is a highly promising anode material, with the advantage of enriched microcrystalline structure characteristics for better lithium storage. Tannin, a secondary product of metabolism during plant growth, has a rich source on earth. But the mechanism of hard carbon obtained from its derivation in lithium-ion batteries has been little studied. This paper successfully applied the hard carbon obtained from tannin as anode and illustrated the relationship between its structure and lithium storage performance. Meanwhile, to further enhance the performance, graphene oxide is skillfully compounded. The contact with the electrolyte and the charge transfer capability are effectively enhanced, then the capacity of PVP-HC is 255.5 mAh g-1 after 200 cycles at a current density of 400 mA g-1, with a capacity retention rate of 91.25%. The present work lays the foundation and opens up ideas for the application of biomass-derived hard carbon in lithium anodes.


Assuntos
Grafite , Lítio , Lítio/química , Grafite/química , Carbono/química , Taninos , Eletrodos , Íons/química , Eletrólitos
14.
Lancet Oncol ; 22(3): 391-401, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33587893

RESUMO

BACKGROUND: Whether extended lymphadenectomy for right colon cancer leads to increased perioperative complications or improves survival is still controversial. This trial aimed to compare the efficacy and safety of complete mesocolic excision (CME) versus D2 dissection in laparoscopic right hemicolectomy for patients with right colon cancer. This article reports the early safety results from the trial. METHODS: This randomised, controlled, phase 3, superiority, trial was done at 17 hospitals in nine provinces of China. Eligible patients were aged 18-75 years with histologically confirmed primary adenocarcinoma located between the caecum and the right third of the transverse colon, without evidence of distant metastases. Central randomisation was done by means of the Clinical Information Management-Central Randomisation System via block randomisation (block size of four). Patients were randomly assigned (1:1) to CME or D2 dissection during laparoscopic right colectomy. Central lymph nodes were dissected in the CME but not in the D2 procedure. Neither investigators nor patients were masked to their group assignment but the quality control committee were masked to group assignment. The primary endpoint was 3-year disease-free survival, but the data for this endpoint are not yet mature; thus, only the secondary outcomes-intraoperative surgical complications and postoperative complications within 30 days of surgery, graded according to the Clavien-Dindo classification, mortality (death from any cause within 30 days of surgery), and central lymph node metastasis rate in the CME group only-are reported in this Article. This early analysis of safety was preplanned. The outcomes were analysed according to a modified intention-to-treat principle (excluding patients who no longer met inclusion criteria after surgery or who did not have surgery). This study is registered with ClinicalTrials.gov, NCT02619942. Study recruitment is complete, and follow-up is ongoing. FINDINGS: Between Jan 11, 2016, and Dec 26, 2019, 1072 patients were enrolled and randomly assigned. After exclusion of 77 patients, 995 patients were included in the modified intention-to-treat population (495 in the CME group and 500 in the D2 dissection group). The postoperative surgical complication rate was 20% (97 of 495 patients) in the CME group versus 22% (109 of 500 patients) in the D2 group (difference, -2·2% [95% CI -7·2 to 2·8]; p=0·39); the frequency of Clavien-Dindo grade I-II complications were similar between groups (91 [18%] vs 92 [18%], difference, -0·0% [95% CI -4·8 to 4·8]; p=1·0) but Clavien-Dindo grade III-IV complications were significantly less frequent in the CME group than in the D2 group (six [1%] vs 17 [3%], -2·2% [-4·1 to -0·3]; p=0·022); no deaths occurred in either group. Of the intraoperative complications, vascular injury was significantly more common in the CME group than in the D2 group (15 [3%] vs six [1%], difference, 1·8 [95% CI 0·04 to 3·6]; p=0·045). Metastases in the central lymph nodes were detected in 13 (3%) of 394 patients who underwent central lymph node biopsy in the CME group; no patient had isolated metastases to central lymph nodes. INTERPRETATION: Although the CME procedure might increase the risk of intraoperative vascular injury, it generally seems to be safe and feasible for experienced surgeons. FUNDING: The Capital Characteristic Clinical Project of Beijing and the Chinese Academy of Medical Sciences.


Assuntos
Adenocarcinoma/cirurgia , Colectomia/mortalidade , Neoplasias do Colo/cirurgia , Laparoscopia/mortalidade , Excisão de Linfonodo/mortalidade , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Neoplasias do Colo/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Adulto Jovem
15.
Hippocampus ; 31(5): 512-521, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33580728

RESUMO

Sodium salicylate, one of the non-steroidal anti-inflammatory drugs, is widely prescribed in the clinic, but a high dose of usage can cause hyperactivity in the central nervous system, including the hippocampus. At present, the neural mechanism underlying the induced hyperactivity is not fully understood, in particular, in the hippocampus under an in vivo condition. In this study, we found that systemic administration of sodium salicylate increased the field excitatory postsynaptic potential slope and the population spike amplitude in a dose-dependent manner in the hippocampal dentate gyrus area of rats with in vivo field potential extracellular recordings, which indicates that sodium salicylate enhances basal synaptic transmission and neural excitation. In the presence of picrotoxin, a GABA-A receptor antagonist, sodium salicylate failed to increase the initial slope of the field excitatory postsynaptic potential and the amplitude of the population spike in vivo. To further explore how sodium salicylate enhances the neural excitation, we made whole-cell patch-clamp recordings from hippocampal slices. We found that perfusion of the slice with sodium salicylate decreased electrically evoked GABA receptor-mediated currents, increased paired-pulse ratio, and lowered frequency and amplitude of miniature inhibitory postsynaptic currents. Together, these results demonstrate that sodium salicylate enhances the neural excitation through suppressing GABAergic synaptic transmission in presynaptic and postsynaptic mechanisms in the hippocampal dentate gyrus area. Our findings may help understand the side effects caused by sodium salicylate in the central nervous system.


Assuntos
Hipocampo , Salicilato de Sódio , Animais , Giro Denteado/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Hipocampo/fisiologia , Ratos , Salicilato de Sódio/farmacologia , Transmissão Sináptica/fisiologia
16.
Mol Pharm ; 18(12): 4290-4298, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34731571

RESUMO

The effect of mucin on ocular bioavailability depends on the extent to which it acts as a barrier or retention site. Mucus penetrating particles (MPPs) can evade the mucus entrapment and associated rapid clearance, but cationic nanoparticles have high adhesion to the mucosa. Both formulations can prolong the drug residence time on the surface of the eyes. The purpose of this work is to compare the effects of mucoadhesion of cationic nanoparticles and mucous permeability of MPPs on ocular bioavailability. Cationic nanosuspensions and drug-core MPP nanosuspensions were developed using the anti-solvent precipitation method. The results of X-ray diffraction revealed that CsA was amorphous. In vitro mucoadhesion evaluation demonstrated that cationic nanosuspensions enhanced the interaction with pig mucin about 5.0-6.0 fold compared to drug-core MPP nanosuspensions. A mucus permeation study by the transwell diffusion system showed that the Papp values of drug-core MPP nanosuspensions were 5.0-10.0 times higher than those of cationic nanosuspensions. In vivo ocular bioavailability evaluation of those CsA formulations was conducted in rabbits using a conventional nanosuspension as a comparison. The CsA concentrations in the cornea following the administration of a cationic nanosuspension and a drug-core MPP nanosuspension were 13,641.10 ng/g and 11,436.07 ng/g, respectively, significantly higher than that of the conventional nanosuspension (8310.762 ng/g). The results showed that both the cationic and MPP nanosuspensions were able to deliver CsA to anterior ocular tissues in effective therapeutic concentrations (10-20 µg/g) with topical drop instillation. The cationic nanosuspension could achieve relatively higher bioavailability than the MPP nanosuspension. The cationic nanosuspension would be a promising ocular drug delivery system.


Assuntos
Ciclosporina/administração & dosagem , Sistemas de Liberação de Medicamentos , Olho/metabolismo , Muco/metabolismo , Nanopartículas/administração & dosagem , Animais , Disponibilidade Biológica , Cristalização , Ciclosporina/química , Ciclosporina/farmacocinética , Difusão , Liberação Controlada de Fármacos , Masculino , Coelhos , Suspensões
17.
J Surg Oncol ; 123 Suppl 1: S36-S42, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33650688

RESUMO

BACKGROUND AND OBJECTIVES: The application of pure natural orifice translumenal endoscopic surgery (NOTES) to intra-abdominal visceral resections remains limited due to the complexity of the dissection. This study aimed to assess the safety and feasibility of laparoscopic right colectomy using a purely transvaginal approach. METHODS: The data of 12 continuous patients with colon neoplasia who underwent transvaginal right colectomy from November 2018 to July 2020 were prospectively collected, and their perioperative events were recorded. RESULTS: The patients' median age was 70.4 years. Four were diagnosed with colon adenoma and eight with adenocarcinoma. The median operative time was 185 min, with a median blood loss of 25 ml. The median time to gas passing was 32.5 h after surgery. The median postoperative hospital stay was 6 days. One operation was converted to hybrid NOTES due to difficulty with the anastomosis, and one was converted to laparoscopic surgery because of vascular injury. Three cases were grades I, II, and III according to the Clavien-Dindo classification. CONCLUSION: Pure NOTES right colectomy using the transvaginal approach is feasible and safe with good short-term outcomes. We recommend this novel technique for highly-selected patients with no more than a D2 dissection performed by experienced colorectal surgeons.


Assuntos
Colectomia/métodos , Neoplasias do Colo/cirurgia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adenoma/patologia , Adenoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/patologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Laparoscopia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Vagina/cirurgia
18.
Analyst ; 146(16): 5055-5060, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34282816

RESUMO

It is imminent to develop a new type of rapid COVID-19 detection method with high sensitivity. Here, we used novel red emission-enhanced carbon dot (CD)-based silica (RCS) spheres as the signals of lateral flow immunochromatography (LFI) to ultrasensitively detect novel severe acute respiratory syndrome coronavirus 2 nucleocapsid proteins (SARS-CoV-2 NPs). The red emission of CDs can be enhanced and enriched in silica spheres by a simple way. The amino ends of the N-ß-(aminoethyl)-γ-aminopropyltrimethoxy anchor carboxyl-rich CDs and enhance the red emission, while the other end is embedded in the silica carrier. Then, the composite silica spheres werecoated with 3-(triethylsilyl) propylamine to protect the CDs, promote bioconjugation and obtain RCS spheres. The optimal emission peaks of the aqueous solution and the solid state of RCS spheres were at 634 nm and 638 nm, respectively, with quantum yields (QYs) of 48.5% and 35.7%, respectively. Their red emission has a wide excitation range (from the ultraviolet region to the red region), and the best excitation wavelength is about 580 nm. Two fluorescence detection modes of the RCS-LFI technology for the SARS-CoV-2 NP assay are available: the simple mode of observation under ultraviolet light has a sensitivity of 100 pg mL-1; the advanced mode of detection under a fluorescence microscope has a sensitivity of 10 pg mL-1. This assay also exhibits the advantages of fast detection speed, high specificity, and simple operation. In addition, the feasibility of this method in actual sample detection was verified in human serum by the standard-addition method, and the results show that the method has excellent practicability. We believe that this method will be a valuable supplement for the diagnosis of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Carbono , Humanos , Imunoensaio , Proteínas do Nucleocapsídeo , Sensibilidade e Especificidade , Dióxido de Silício
19.
Analyst ; 146(2): 706-713, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33216074

RESUMO

Here a novel strategy is reported of assembling silanized carbon dots (CDs) with porous silica templates to form fluorescent CD-based silica (FCS) colloids with uniformly packed CDs throughout the silica matrix. Dendritic silica spheres with highly accessible central-radial pores are adopted as a powerful absorbent host, which can form Si-O bonds with silane to directly fix the silanized CDs. The appropriate loading content of CDs on the inner surface of dendritic silica spheres is beneficial for the maximum fluorescence intensity of FCS colloids. High-quality silanized CDs endow multiple CD embedded silica spheres with excellent properties, including good fluorescence performance, excellent colloidal/optical stabilities and convenient biofunctionalization. The integration of these FCS colloids with a lateral flow strip platform provides an ultra-sensitive, specific and robust immunoassay method for the Zika NS1 protein with a visual detection limit of 10 pg mL-1, and has been successfully applied to the detection of Zika virus in clinical samples. In addition, we also prepared conventional Au NP-based lateral flow test strips and applied them to the detection of Zika NS1 protein. By comparison, the detection limit of immunofluorescent CD-based silica (iFCS)-based lateral flow test strips is 100-fold lower than that of Au NP-based lateral flow strips.


Assuntos
Carbono/química , Imunoensaio/métodos , Limite de Detecção , Nanopartículas/química , Dióxido de Silício/química , Zika virus/isolamento & purificação , Coloides , Humanos
20.
Phys Chem Chem Phys ; 23(46): 26241-26249, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34787123

RESUMO

CO2 reduction catalysis plays an important role in the process of converting harmful exhaust gas into useful fuels. However, the product complexity and the difficult hydrogenation in critical steps make it difficult to find a suitable catalyst for CO2 reduction. In this work, we report homo/hetero bimetal embedded in two-dimensional materials for electrocatalysis and discovered a new descriptor. We chose ß12-borophene accommodating two transition metal atoms for efficient CO2RR as a model system. We found that MnCo and VV systems are promising for CO2 reduction with good stability and high selectivity over HER. Through least absolute shrinkage and selection operator (LASSO) regression, we discovered a new integrated descriptor containing the spin moment of the metals and the descriptor is linked with the performance of the first step of CO2 hydrogenation. The MnCo system could catalyze a C1 process with low free energy change of the rate determining step. The VV system could also conduct the C2 process with low free energy change of the rate determining step. Bader charge analysis shows the ability of the borophene substrate to provide or hold electrons. This work demonstrates homonuclear and heteronuclear biatomic catalysts with high activity for CO2RR.

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