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1.
Nature ; 621(7979): 506-510, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37648858

RESUMO

Graphitic electrode is commonly used in electrochemical reactions owing to its excellent in-plane conductivity, structural robustness and cost efficiency1,2. It serves as prime electrocatalyst support as well as a layered intercalation matrix2,3, with wide applications in energy conversion and storage1,4. Being the two-dimensional building block of graphite, graphene shares similar chemical properties with graphite1,2, and its unique physical and chemical properties offer more varieties and tunability for developing state-of-the-art graphitic devices5-7. Hence it serves as an ideal platform to investigate the microscopic structure and reaction kinetics at the graphitic-electrode interfaces. Unfortunately, graphene is susceptible to various extrinsic factors, such as substrate effect8-10, causing much confusion and controversy7,8,10,11. Hereby we have obtained centimetre-sized substrate-free monolayer graphene suspended on aqueous electrolyte surface with gate tunability. Using sum-frequency spectroscopy, here we show the structural evolution versus the gate voltage at the graphene-water interface. The hydrogen-bond network of water in the Stern layer is barely changed within the water-electrolysis window but undergoes notable change when switching on the electrochemical reactions. The dangling O-H bond protruding at the graphene-water interface disappears at the onset of the hydrogen evolution reaction, signifying a marked structural change on the topmost layer owing to excess intermediate species next to the electrode. The large-size suspended pristine graphene offers a new platform to unravel the microscopic processes at the graphitic-electrode interfaces.

2.
Environ Sci Technol ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838251

RESUMO

Recent discoveries indicate that several insect larvae are capable of ingesting and biodegrading plastics rapidly and symbiotically, but the ecological adaptability of the larval gut microbiome to microplastics (MPs) remains unclear. Here, we described the gut microbiome assemblage and MP biodegradation of superworms (Zophobas atratus larvae) fed MPs of five major petroleum-based polymers (polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate) and antibiotics. The shift of molecular weight distribution, characteristic peaks of C═O, and metabolic intermediates of residual polymers in egested frass proved depolymerization and biodegradation of all MPs tested in the larval intestines, even under antibiotic suppression. Superworms showed a wide adaptation to the digestion of the five polymer MPs. Antibiotic suppression negatively influenced the survival rate and plastic depolymerization patterns. The larval gut microbiomes differed from those fed MPs and antibiotics, indicating that antibiotic supplementation substantially shaped the gut microbiome composition. The larval gut microbiomes fed MPs had higher network complexity and stability than those fed MPs and antibiotics, suggesting that the ecological robustness of the gut microbiomes ensured the functional adaptability of larvae to different MPs. In addition, Mantel's test indicated that the gut microbiome assemblage was obviously related to the polymer type, the plastic degradability, antibiotic stress, and larval survival rate. This finding provided novel insights into the self-adaptation of the gut microbiome of superworms in response to different MPs.

3.
Environ Sci Technol ; 58(15): 6647-6658, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38563431

RESUMO

The biodegradation of polypropylene (PP), a highly persistent nonhydrolyzable polymer, by Tenebrio molitor has been confirmed using commercial PP microplastics (MPs) (Mn 26.59 and Mw 187.12 kDa). This confirmation was based on the reduction of the PP mass, change in molecular weight (MW), and a positive Δδ13C in the residual PP. A MW-dependent biodegradation mechanism was investigated using five high-purity PP MPs, classified into low (0.83 and 6.20 kDa), medium (50.40 and 108.0 kDa), and high (575.0 kDa) MW categories to access the impact of MW on the depolymerization pattern and associated gene expression of gut bacteria and the larval host. The larvae can depolymerize/biodegrade PP polymers with high MW although the consumption rate and weight losses increased, and survival rates declined with increasing PP MW. This pattern is similar to observations with polystyrene (PS) and polyethylene (PE), i.e., both Mn and Mw decreased after being fed low MW PP, while Mn and/or Mw increased after high MW PP was fed. The gut microbiota exhibited specific bacteria associations, such as Kluyvera sp. and Pediococcus sp. for high MW PP degradation, Acinetobacter sp. for medium MW PP, and Bacillus sp. alongside three other bacteria for low MW PP metabolism. In the host transcriptome, digestive enzymes and plastic degradation-related bacterial enzymes were up-regulated after feeding on PP depending on different MWs. The T. molitor host exhibited both defensive function and degradation capability during the biodegradation of plastics, with high MW PP showing a relatively negative impact on the larvae.


Assuntos
Microbiota , Tenebrio , Animais , Tenebrio/metabolismo , Tenebrio/microbiologia , Plásticos , Polipropilenos/metabolismo , Microplásticos , Peso Molecular , Poliestirenos , Larva/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental
4.
Clin Oral Investig ; 28(7): 395, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916666

RESUMO

BACKGROUND: While the accurate prediction of the overall survival (OS) in patients with submandibular gland cancer (SGC) is paramount for informed therapeutic planning, the development of reliable survival prediction models has been hindered by the rarity of SGC cases. The purpose of this study is to identify key prognostic factors for OS in SGC patients using a large database and construct decision tree models to aid the prediction of survival probabilities in 12, 24, 60 and 120 months. MATERIALS AND METHODS: We performed a retrospective cohort study using the Surveillance, Epidemiology and End Result (SEER) program. Demographic and peri-operative predictor variables were identified. The outcome variables overall survival at 12-, 24-, 60, and 120 months. The C5.0 algorithm was utilized to establish the dichotomous decision tree models, with the depth of tree limited within 4 layers. To evaluate the performances of the novel models, the receiver operator characteristic (ROC) curves were generated, and the metrics such as accuracy rate, and area under ROC curve (AUC) were calculated. RESULTS: A total of 1,705, 1,666, 1,543, and 1,413 SGC patients with a follow up of 12, 24, 60 and 120 months and exact survival status were identified from the SEER database. Predictor variables of age, sex, surgery, radiation, chemotherapy, tumor histology, summary stage, metastasis to distant lymph node, and marital status exerted substantial influence on overall survival. Decision tree models were then developed, incorporating these vital prognostic indicators. Favorable consistency was presented between the predicted and actual survival statuses. For the training dataset, the accuracy rates for the 12-, 24-, 60- and 120-month survival models were 0.866, 0.767, 0.737 and 0.797. Correspondingly, the AUC values were 0.841, 0.756, 0.725, and 0.774 for the same time points. CONCLUSIONS: Based on the most important predictor variables identified using the large, SEER database, decision tree models were established that predict OS of SGC patients. The models offer a more exhaustive evaluation of mortality risk and may lead to more personalized treatment strategies.


Assuntos
Árvores de Decisões , Programa de SEER , Neoplasias da Glândula Submandibular , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Glândula Submandibular/patologia , Neoplasias da Glândula Submandibular/terapia , Idoso , Prognóstico , Adulto , Taxa de Sobrevida , Estadiamento de Neoplasias , Algoritmos , Análise de Sobrevida
5.
J Environ Manage ; 358: 120832, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599089

RESUMO

Polyethylene (PE) is the most productive plastic product and includes three major polymers including high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) variation in the PE depends on the branching of the polymer chain and its crystallinity. Tenebrio obscurus and Tenebrio molitor larvae biodegrade PE. We subsequently tested larval physiology, gut microbiome, oxidative stress, and PE degradation capability and degradation products under high-purity HDPE, LLDPE, and LDPE powders (<300 µm) diets for 21 days at 65 ± 5% humidity and 25 ± 0.5 °C. Our results demonstrated the specific PE consumption rates by T. molitor was 8.04-8.73 mg PE ∙ 100 larvae-1⋅day-1 and by T. obscurus was 7.68-9.31 for LDPE, LLDPE and HDPE, respectively. The larvae digested nearly 40% of the ingested three PE and showed similar survival rates and weight changes but their fat content decreased by 30-50% over 21-day period. All the PE-fed groups exhibited adverse effects, such as increased benzoquinone concentrations, intestinal tissue damage and elevated oxidative stress indicators, compared with bran-fed control. In the current study, the digestive tract or gut microbiome exhibited a high level of adaptability to PE exposure, altering the width of the gut microbial ecological niche and community diversity, revealing notable correlations between Tenebrio species and the physical and chemical properties (PCPs) of PE-MPs, with the gut microbiome and molecular weight change due to biodegradation. An ecotoxicological simulation by T.E.S.T. confirmed that PE degradation products were little ecotoxic to Daphnia magna and Rattus norvegicus providing important novel insights for future investigations into the environmentally-friendly approach of insect-mediated biodegradation of persistent plastics.


Assuntos
Biodegradação Ambiental , Larva , Microplásticos , Polietileno , Tenebrio , Animais , Tenebrio/metabolismo , Polietileno/metabolismo , Microplásticos/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Estresse Oxidativo
6.
Eur J Nucl Med Mol Imaging ; 50(3): 881-891, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36301324

RESUMO

PURPOSE: To compare PET/CT, MRI and ultrasonography in detecting recurrence of nasopharyngeal carcinoma and identify their benefit in staging, contouring and overall survival (OS). METHODS: Cohort A included 1453 patients with or without histopathology-confirmed local recurrence, while cohort B consisted of 316 patients with 606 histopathology-confirmed lymph nodes to compare the sensitivities and specificities of PET/CT, MRI and ultrasonography using McNemar test. Cohorts C and D consisted of 273 patients from cohort A and 267 patients from cohort B, respectively, to compare the distribution of PET/CT-based and MRI-based rT-stage and rN-stage and the accuracy of rN-stage using McNemar test. Cohort E included 30 random patients from cohort A to evaluate the changes in contouring with or without PET/CT by related-samples T test or Wilcoxon rank test. The OS of 61 rT3-4N0M0 patients staged by PET/CT plus MRI (cohort F) and 67 MRI-staged rT3-4N0M0 patients (cohort G) who underwent similar salvage treatment were compared by log-rank test and Cox regression. RESULTS: PET/CT had similar specificity to MRI but higher sensitivity (93.9% vs. 79.3%, P < 0.001) in detecting local recurrence. PET/CT, MRI and ultrasonography had comparable specificities, but PET/CT had greater sensitivity than MRI (90.9% vs. 67.6%, P < 0.001) and similar sensitivity to ultrasonography in diagnosing lymph nodes. According to PET/CT, more patients were staged rT3-4 (82.8% vs. 68.1%, P < 0.001) or rN + (89.9% vs. 69.3%, P < 0.001), and the rN-stage was more accurate (90.6% vs. 73.8%, P < 0.001). Accordingly, the contours of local recurrence were more precise (median Dice similarity coefficient 0.41 vs. 0.62, P < 0.001) when aided by PET/CT plus MRI. Patients staged by PET/CT plus MRI had a higher 3-year OS than patients staged by MRI alone (85.5% vs. 60.4%, P = 0.006; adjusted HR = 0.34, P = 0.005). CONCLUSION: PET/CT more accurately detected and staged recurrence of nasopharyngeal carcinoma and accordingly complemented MRI, providing benefit in contouring and OS.


Assuntos
Neoplasias Nasofaríngeas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Fluordesoxiglucose F18 , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/terapia , Terapia de Salvação , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/terapia , Recidiva Local de Neoplasia/patologia , Imageamento por Ressonância Magnética , Sensibilidade e Especificidade , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/terapia , Estadiamento de Neoplasias
7.
Environ Sci Technol ; 57(8): 3031-3041, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36790312

RESUMO

Tenebrio molitor and Tenebrio obscurus (Coleoptera: Tenebrionidae) larvae are two commercial insects that eat plant and crop residues as diets and also biodegrade synthetic plastics polyethylene (PE). We examined biodegradation of low-density PE (LDPE) foam (Mn = 28.9 kDa and Mw = 342.0 kDa) with and without respective co-diets, i.e., wheat brain (WB) or corn flour (CF), corn straw (CS), and rice straw (RS) at 4:1 (w/w), and their gut microbiome and genetic metabolic functional groups at 27.0 ± 0.5 °C after 28 days of incubation. The presence of co-diets enhanced LDPE consumption in both larvae and broad-depolymerized the ingested LDPE. The diet type shaped gut microbial diversity, potential pathways, and metabolic functions. The sequence of effectiveness of co-diets was WB or CF > CS > RS for larval development and LDPE degradation. Co-occurrence networks indicated that the larvae co-fed with LDPE displayed more complex correlations of gut microbiome than the larvae fed with single diets. The primary diet of WB or CF and crop residues CS and RS provided energy and nitrogen source to significantly enhance LDPE biodegradation with synergistic activities of the gut microbiota. For the larvae fed LDPE and LDPE plus co-diets, nitrogen fixation function was stimulated compared to normal diets and associated with LDPE biodegradation.


Assuntos
Besouros , Microbioma Gastrointestinal , Tenebrio , Animais , Larva/metabolismo , Tenebrio/metabolismo , Polietileno , Poliestirenos , Carbono/metabolismo , Besouros/metabolismo , Dieta
8.
Environ Res ; 224: 115513, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36801232

RESUMO

One of the most prevalent heavy metals found in rural sewage is Zn(II), while its effect on simultaneous nitrification, denitrification and phosphorus removal (SNDPR) remains unclear. In this work, the responses of SNDPR performance to long-term Zn(II) stress were investigated in a cross-flow honeycomb bionic carrier biofilm system. The results indicated that Zn(II) stress at 1 and 5 mg L-1 could increase nitrogen removal. Maximum ammonia nitrogen, total nitrogen, and phosphorus removal efficiencies of up to 88.54%, 83.19%, and 83.65% were obtained at Zn(II) concentration of 5 mg L-1. The functional genes, such as archaeal amoA, bacterial amoA, NarG, NirS, NapA, and NirK, also reached the highest value at 5 mg L-1 Zn(II), with the absolute abundances of 7.73 × 105, 1.57 × 106, 6.68 × 108, 1.05 × 109, 1.79 × 108, and 2.09 × 108 copies·g-1 dry weight, respectively. The neutral community model demonstrated that deterministic selection was responsible for the system's microbial community assembly. Additionally, response regimes with extracellular polymeric substances and cooperation among microorganisms facilitated the stability of the reactor effluent. Overall, the findings of this paper contribute to improving the efficiency of wastewater treatment.


Assuntos
Microbiota , Nitrificação , Desnitrificação , Fósforo , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Nitrogênio , Desempenho Físico Funcional , Zinco , Eliminação de Resíduos Líquidos/métodos
9.
Antimicrob Agents Chemother ; 66(1): e0146521, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34780266

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is one of the most fatal diseases in the world. Methylenetetrahydrofolate reductase (MTHFR) catalyzes the production of 5-methyltetrahydrofolate (5-CH3-THF), which is required for the de novo biosynthesis of methionine in bacteria. Here, we identified Rv2172c as an MTHFR in M. tuberculosis through in vitro and in vivo analyses and determined that the protein is essential for the in vitro growth of the bacterium. Subsequently, we constructed rv2172c R159N and L214A mutants in M. tuberculosis and found that these mutants were more sensitive to the antifolates para-aminosalicylic acid (PAS) and sulfamethoxazole (SMX). Combining biochemical and genetic methods, we found that rv2172c R159N or L214A mutation impaired methionine production, leading to increased susceptibility of M. tuberculosis to PAS, which was largely restored by adding exogenous methionine. Moreover, overexpression of rv2172c in M. tuberculosis could increase methionine production and lead to PAS resistance. This research is the first to identify an MTHFR in M. tuberculosis and reveals that the activity of this enzyme is associated with susceptibility to antifolates. These findings have particular value for antitubercular drug design for the treatment of drug-resistant TB.


Assuntos
Ácido Aminossalicílico , Mycobacterium tuberculosis , Ácido Aminossalicílico/metabolismo , Ácido Aminossalicílico/farmacologia , Antituberculosos/metabolismo , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/metabolismo
10.
Eur J Nucl Med Mol Imaging ; 49(3): 980-991, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34468782

RESUMO

BACKGROUND: To test the advantages of positron emission tomography and computed tomography (PET/CT) for diagnosing lymph nodes and staging nasopharyngeal carcinoma and to investigate its benefits for survival and treatment decisions. METHODS: The performance of PET/CT and magnetic resonance imaging (MRI) in diagnosis was compared based on 460 biopsied lymph nodes. Using the propensity matching method, survival differences of T3N1M0 patients with (n = 1093) and without (n = 1377) PET/CT were compared in diverse manners. A radiologic score model was developed and tested in a subset of T3N1M0 patients. RESULTS: PET/CT performed better than MRI with higher sensitivity, accuracy, and area under the receiver operating characteristic curve (96.7% vs. 88.5%, p < 0.001; 88.0% vs. 81.1%, p < 0.001; 0.863 vs. 0.796, p < 0.05) in diagnosing lymph nodes. Accordingly, MRI-staged T3N0-3M0 patients showed nondifferent survival rates, as they were the same T3N1M0 if staged by PET/CT. In addition, patients staged by PET/CT and MRI showed higher survival rates than those staged by MRI alone (p < 0.05), regardless of the Epstein-Barr virus DNA load. Interestingly, SUVmax-N, nodal necrosis, and extranodal extension were highly predictive of survival. The radiologic score model based on these factors performed well in risk stratification with a C-index of 0.72. Finally, induction chemotherapy showed an added benefit (p = 0.006) for the high-risk patients selected by the model but not for those without risk stratification (p = 0.78). CONCLUSION: PET/CT showed advantages in staging nasopharyngeal carcinoma due to a more accurate diagnosis of lymph nodes and this contributed to a survival benefit. PET/CT combined with MRI provided prognostic factors that could identify high-risk patients and guide individualized treatment.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Infecções por Vírus Epstein-Barr/patologia , Fluordesoxiglucose F18 , Herpesvirus Humano 4 , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/terapia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Sensibilidade e Especificidade
11.
Eur Radiol ; 32(6): 3649-3660, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34989842

RESUMO

OBJECTIVES: We aimed to develop and validate radiologic scores from [18F]FDG PET/CT and MRI to guide individualized induction chemotherapy (IC) for patients with T3N1M0 nasopharyngeal carcinoma (NPC). METHODS: A total of 542 T3N1M0 patients who underwent pretreatment [18F]FDG PET/CT and MRI were enrolled in the training cohort. A total of 174 patients underwent biopsy of one or more cervical lymph nodes. Failure-free survival (FFS) was the primary endpoint. The radiologic score, which was calculated according to the number of risk factors from the multivariate model, was used for risk stratification. The survival difference of patients undergoing concurrent chemoradiotherapy (CCRT) with or without IC was then compared in risk-stratified subgroups. Another cohort from our prospective clinical trial (N = 353, NCT03003182) was applied for validation. RESULTS: The sensitivity of [18F]FDG PET/CT was better than that of MRI (97.7% vs. 87.1%, p < 0.001) for diagnosing histologically proven metastatic cervical lymph nodes. Radiologic lymph node characteristics were independent risk factors for FFS (all p < 0.05). High-risk patients (n = 329) stratified by radiologic score benefited from IC (5-year FFS: IC + CCRT 83.5% vs. CCRT 70.5%; p = 0.0044), while low-risk patients (n = 213) did not. These results were verified again in the validation cohort. CONCLUSIONS: T3N1M0 patients were accurately staged by both [18F]FDG PET/CT and MRI. The radiologic score can correctly identify high-risk patients who can gain additional survival benefit from IC and it can be used to guide individualized treatment of T3N1M0 NPC. KEY POINTS: • [18F]FDG PET/CT was more accurate than MRI in diagnosing histologically proven cervical lymph nodes. • Radiologic lymph node characteristics were reliable independent risk factors for FFS in T3N1M0 nasopharyngeal carcinoma patients. • High-risk patients identified by the radiologic score based on [18F]FDG PET/CT and MRI could benefit from the addition of induction chemotherapy.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Nasofaríngeas , Quimiorradioterapia/métodos , Humanos , Quimioterapia de Indução , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
12.
Environ Res ; 206: 112630, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973940

RESUMO

With the acceleration of urbanization, the proportion of surface imperviousness is increasing continuously in cities, resulting in frequent waterlogging disasters. In this context, storm water management, based on the low-impact development (LID) concept, offers an effective measure for the management of urban storm waters. First, the storm water management model (SWMM) was built for a typical cold climate city (Changchun) in China. Next, the two-stage calibrated model was employed to explore the surface runoff and storm sewer control effects of four LID combination plans. Finally, these plans were put through a "cost-benefit" evaluation through an analytic hierarchy process. According to the results, after using four LID plans, the reduction rates of peak runoff exceeded 40% and the problem of overflow load of the storm sewage was significantly mitigated. The infiltration-oriented Plan I proved to be the optimal plan, with the lowest proportions of the overflow nodes and full-load pipe sections in each return period, as well as with maximum overall performance. This study offers technical and conformed methodological support to cold cities for the prevention and control of waterlogging disasters and recycling of rainwater resources.


Assuntos
Chuva , Movimentos da Água , China , Cidades , Clima Frio , Urbanização
13.
Zhongguo Zhong Yao Za Zhi ; 47(18): 4877-4885, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164897

RESUMO

Appropriate light intensity is favorable for the photosynthesis, biomass accumulation, key enzyme activity, and secondary metabolite synthesis of medicinal plants. This study aims to explore the influence of light intensity on growth and quality of Panax quinquefolius. To be specific, sand culture experiment was carried out in a greenhouse under the light intensity of 40, 80, 120, and 160 µmol·m~(-2)·s~(-1), respectively. The growth indexes, photosynthetic characteristics, content of 6 ginsenosides of the 3-year-old P. quinquefolius were determined, and the expression of ginsenoside synthesis-related enzyme genes in leaves, main roots, and fibrous roots was determined. The results showed that the P. quinquefolius growing at 80 µmol·m~(-2)·s~(-1) light intensity had the most biomass and the highest net photosynthetic rate. The total biomass of P. quinquefolius treated with 120 µmol·m~(-2)·s~(-1) light intensity was slightly lower than that with 80 µmol·m~(-2)·s~(-1). The root-to-shoot ratio in the treatment with 120 µmol·m~(-2)·s~(-1) light intensity was up to 6.86, higher than those in other treatments(P<0.05),and the ginsenoside content in both aboveground and underground parts of P. quinquefolius in this treatment was the highest, which was possibly associated with the high expression of farnesylpyrophosphate synthase(FPS), squalene synthase(SQS), squalene epoxidase(SQE), oxidosqualene cyclase(OSC), dammarenediol-Ⅱ synthase(DS), and P450 genes in leaves and SQE and DS genes in main roots. In addition, light intensities of 120 and 160 µmol·m~(-2)·s~(-1) could promote PPD-type ginsenoside synthesis in leaves by triggering up-regulation of the expression of upstream ginsenoside synthesis genes. The decrease in underground biomass accumulation of the P. quinquefolius grown under weak light(40 µmol·m~(-2)·s~(-1)) and strong light(160 µmol·m~(-2)·s~(-1)) was possibly attributed to the low net photosynthetic rate, stomatal conductance, and transpiration rate in leaves. In the meantime, the low expression of SQS, SQE, OSC, and DS genes in the main roots might led to the decrease in ginsenoside content. However, there was no significant correlation between the ginsenoside content and the expression of synthesis-related genes in the fibrous roots of P. quinquefolius. Therefore, the light intensity of 80 and 120 µmol·m~(-2)·s~(-1) is beneficial to improving yield and quality of P. quinquefolius. The above findings contributed to a theoretical basis for reasonable shading in P. quinquefolius cultivation, which is of great significance for improving the yield and quality of P. quinquefolius through light regulation.


Assuntos
Ginsenosídeos , Panax , Farnesil-Difosfato Farnesiltransferase/metabolismo , Panax/metabolismo , Raízes de Plantas/metabolismo , Areia , Esqualeno Mono-Oxigenase
14.
BMC Genomics ; 22(1): 668, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525971

RESUMO

OBJECTIVE: From genome-wide association studies, brain-derived neurotrophic factor (BDNF) locus on chromosome 11 was the only SNP associated with both smoking and body mass index (BMI) in European, African and Asian population. This study aims to explore the unique genetic predisposition to obesity in former smokers by examining the effects of BDNF on BMI and waist circumference (WC). METHODS: The study design is case-control study with a cohort validation in supplementary. We included 15,072 ethnic Chinese participants in the Guangzhou Biobank Cohort Study (GBCS) with data of four BDNF SNPs related to both BMI and smoking behavior. We used baseline smoke exposure data in 2003-2007 and follow-up outcomes of general obesity (by BMI) and central obesity (WC) in 2008-2012. Odds ratios (ORs) and 95% confidence intervals (CIs) for general obesity and central obesity associated with these SNPs were derived from logistic regression. RESULTS: Of 15,072 participants (3169 men and 11,903 women), 1664 (11.0%) had general and 7868 (52.2%) had central obesity. In 1233 former smokers, the rs6265 GG, versus AA, genotype was associated with higher risks of general obesity (OR = 1.79, 95% CI = 1.06-3.01) and central obesity (OR = 2.08, 95% CI = 1.47-2.92) after adjustment. These associations were not significant in never or current smokers. In former heavy (≥20 cigarettes/day) smokers, the rs6265 GG genotype showed a higher odds for general obesity (OR = 2.15, 95% CI = 1.05-4.40), while no association was found in former light (1-9 cigarettes/day) smokers. Similar results were found for the association of rs6265 with central obesity and for the associations of other two BDNF SNPs (rs4923457 and rs11030104) with both general and central obesity. CONCLUSIONS: We firstly identified the genetic predisposition (BDNF SNPs) to general and central obesity in former smokers, particularly in former heavy smokers. The different associations of the SNPs for general/central obesity in different smoke exposure groups may be related to the competitive performance of the sites and epigenetic modification, which needs further study.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Estudo de Associação Genômica Ampla , Índice de Massa Corporal , Fator Neurotrófico Derivado do Encéfalo/genética , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Obesidade/genética , Fumantes
15.
Anal Chem ; 93(12): 5301-5308, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33739818

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are regarded as promising electrochemiluminescent (ECL) emitters owing to their high quantum efficiency and inexpensive production. Despite the fact that the ECL properties of the pure PAH microcrystal (such as rubrene microcrystals, Rub MCs) have gained extensive attention, it is a challenge in controlling the morphology and size to reduce the inner filter effect. Herein, an advanced ECL emitter of palladium nanoparticle-functionalized hollow PAH-metal nanocubes was prepared by an in situ redox deposition method (the resultant nanocomposites were abbreviated as Pd-Rub-Ag@Au nanocubes). Specifically, the rubrene-decorated Ag@Au nanocubes (Rub-Ag@Au nanocubes) were prepared using the Ag@Au nanocubes as a template and a rubrene cation radical (Rub•+) as a reductant, and then Pd nanoparticles (Pd NPs) were in situ reduced on the surface of Rub-Ag@Au nanocubes. Impressively, compared with the Rub MCs, Pd-Rub-Ag@Au nanocubes showed uniform size and significantly enhanced ECL efficiency and intensity in the aqueous media. As a proof-of-concept, the Pd-Rub-Ag@Au nanocube-based ECL biosensing platform combined with a multisite-anchored DNA nanomachine was constructed for ochratoxin A (OTA, a type of mycotoxin) detection. The DNA nanomachine covered with high-density recognizing sequences could operate toehold-mediated strand displacement amplification on the sensing platform and promote the movement efficiency and velocity greatly. Due to the advanced performance of Pd-Rub-Ag@Au nanocubes and high recognition efficiency of the DNA nanomachine, the proposed biosensor for OTA detection can achieve a detection limit of 4.7 fg/mL ranging from 0.01 to 100 pg/mL, which offers an ingenious method for the further application of PAHs.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Micotoxinas , DNA , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Medições Luminescentes
16.
BMC Cancer ; 21(1): 860, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315423

RESUMO

BACKGROUND: The psychometric properties of the simplified Chinese version of the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) have not been assessed. Therefore, we aimed to assess its validity, reliability, and responsiveness. PATIENTS AND METHODS: A Chinese version of the PRO-CTCAE and the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (QLQ-C30) were distributed to 1580 patients from four cancer hospitals in China. Validity assessments included construct validity, measured by Pearson's correlations and confirmatory factor analysis (CFA), and known-groups validity, measured by t-tests. The assessment of reliability included internal consistency, measured by Cronbach's ɑ, and test-retest reliability, measured by the intraclass correlation (ICC). Responsiveness was assessed by standardized response means (SRMs). RESULTS: Data from 1555 patients who completed the instruments were analyzed. The correlations were high between PRO-CTCAE items and parallel QLQ-C30 symptom scales (r > 0.60, p < 0.001), except for fatigue (severity: r = 0.49). Moreover, CFA showed the PRO-CTCAE structure was a good fit with the data (Root Mean Square Error of Approximation = 0.046). Known-groups validity was also confirmed. Cronbach's ɑ of all item clusters were greater than 0.9 and the median test-retest reliability coefficients of the 38 items were 0.85 (range = 0.71-0.91). In addition, the SRMs of PRO-CTCAE items were greater than 0.8, indicating strong responsiveness. CONCLUSION: The simplified Chinese version of the PRO-CTCAE showed good reliability, validity, and responsiveness.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Medidas de Resultados Relatados pelo Paciente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto Jovem
17.
Exp Cell Res ; 391(2): 111983, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32268136

RESUMO

OBJECTIVE: To explore the effects of breast cancer (BC)-derived exosomes on invasion and migration of BC cells. METHODS: Exosomes (Exo-MA, Exo-M7, Exo-M1) were extracted from normal breast epithelial cells (MCF-10A), BC cells (MCF-7/MDA-MB-231) and BC cells with miR-146a overexpression or knockdown using multi-step differential centrifugation. Morphologies and sizes of exosomes were observed by transmission electron microscope (TEM) and particle size analysis respectively. BC mouse models were injected with DIR labeled Exo-MA, Exo-M7 or Exo-M1. The epithelial-mesenchymal transition (EMT) in BC cells was determined by PCR and Western blot. PKH67 labeled Exo-MA, Exo-M7 and Exo-M1 were incubated with NFs or MCF-7 to measure the activation of CAFs. Cell invasion and migration abilities were determined by scratch test and Transwell assay. RESULTS: Exo-MA, Exo-M7, Exo-M1 were successfully extracted with positive expressions of Alix, CD63 and TSG101. Contents of Ki67, N-cadherin, Vimentin and Snail-1 were increased but E-cadherin was decreased, compared to Exo-MA group. Exo-M7 or Exo-M1 could increase BC cell proliferation and enhance EMT in nude mouse. Exo-M7 and Exo-M1 could accelerate the transformation of NFs into CAFs and promote the recruitment of CAFs in MCF-7. Transfection of miR-146a could promote the transformation of NFs into CAFs and promote cell invasion and migration of MCF-7 cells. As a target gene of miR-146a, TXNIP could inhibit the activation of CAFs. miR-146a overexpression or TXNIP silence enhance the activation of Wnt signal pathway. CONCLUSION: BC-derived exosomes promote the activation of CAFs through miR-146a/TXNIP axis to activate Wnt pathway, which in turn enhances invasion and metastasis of BC cells.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Exossomos/patologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Microambiente Tumoral/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Movimento Celular , Proliferação de Células , Exossomos/genética , Exossomos/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Cancer Cell Int ; 20: 344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742191

RESUMO

BACKGROUND: Concurrent chemoradiotherapy is the common first-line treatment for patients with advanced cervical cancer. However, radioresistance remains a major clinical challenge, which results in recurrence and poor survival. Many studies have shown the potential of Delta-like Ligand 4 (DLL4) as a novel prognostic biomarker and therapeutic target in many solid tumors. Previously, we have found that high DLL4 expression in tumor cells may predict the pelvic lymph node metastasis and poor prognosis in patients with cervical cancer. In our present study, we further studied the effects of DLL4 on the biological behavior and radiosensitivity of cervical cancer cells. METHODS: The expression of DLL4 and epithelial-mesenchymal transition (EMT) phenotype markers in cervical cancer cell lines or tissues were detected using Western blotting, and the expression of DLL4 mRNA in cervical cancer cell lines or tissues was detected using Quantitative real-time PCR. The effect of DLL4 on cell proliferation, migration, and radiosensitivity was evaluated using the CCK8 assay, flow cytometry, Transwell assays for cell invasion and migration, and Immunofluorescence staining in vitro. RESULTS: The expression of DLL4 in radiotherapy-resistant SiHa cells was significantly higher than that in radiotherapy-sensitive Me-180 cells. Furthermore, downregulation of DLL4 enhanced the radiosensitivity of SiHa and Caski cells via the inhibition of cell proliferation, promotion of radiation-induced apoptosis, and inhibition of the DNA damage repair. Moreover, downregulation of DLL4 inhibited the EMT and reduced the proliferation, invasion, and migration ability in SiHa and Caski cells. Consistent with the DLL4 expression in the cell lines, the expression of DLL4 in the tissues of the radioresistant group was also higher than that of the radiosensitive group. CONCLUSIONS: Downregulation of DLL4 inhibited the progression and increased the radiosensitivity in cervical cancer cells by reversing EMT. These results indicated the promising prospect of DLL4 against the radioresistance and metastasis of cervical cancer and its potential as a predictive biomarker for radiosensitivity and prognosis in patients with cervical cancer patients receiving concurrent chemoradiotherapy (cCRT).

19.
Environ Sci Technol ; 54(5): 2821-2831, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013402

RESUMO

Plastics waste and microplastics including polyethylene (PE) and polystyrene (PS) have been an environmental concern for years. Recent research has revealed that larvae of Galleria mellonella are capable of biodegrading low density PE film. In this study, we tested the feasibility of enhancing larval survival and the effect of supplementing the co-diet on plastic degradation by feeding the larvae beeswax or wheat bran as a co-diet. Significant mass loss of plastic was observed over a 21-day period, i.e., with respective consumption of 0.88 and 1.95 g by 150 larvae fed only either PS or PE. The formation of C═O and C-O containing functional groups and long chain fatty acids as the metabolic intermediates of plastics in the residual polymers indicated depolymerization and biodegradation. Supplementing beeswax and bran increased the survival rates but decreased the consumption of plastic. The changes in the gut microbiome revealed that Bacillus and Serratia were significantly associated with the PS and PE diets. Beeswax and bran showed different shaping effects on the core gut microbiome of larvae fed the PE and PS. These results suggest that supplementing the co-diet affected the physiological properties of the larvae and plastic biodegradation and shaped the core gut microbiome.


Assuntos
Microbioma Gastrointestinal , Mariposas , Animais , Suplementos Nutricionais , Larva , Plásticos , Polietileno , Poliestirenos
20.
Clin Endocrinol (Oxf) ; 91(6): 759-769, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31420887

RESUMO

OBJECTIVE: In this study, a genetic risk score (GRS) for the body mass index (BMI) tested and built using a large sample of Chinese individuals aged at least 50 years in southern China. We collected information regarding the participants' weights at 20 years of age and middle age and tested the BMI-GRS effect modes. METHODS: This study involved a prospective study design. The genetic data of the participants in from the Guangzhou Biobank Cohort Study and selected BMI-related single-nucleotide polymorphisms (SNPs) were used to establish the GRS. RESULTS: We included 13 597 participants with 12 SNPs. After adjusting for covariates, the high-GRS group was 36% (95% CI: 25%-48%) and 34% (95% CI: 23%-47%) more likely of being overweight at baseline and follow-up, respectively, and 56% (95% CI: 34%-82%) and 49% (95% CI: 29%-72%) more likely of being obese at baseline and follow-up, respectively, compared with the low-GRS group (P-value for all trends <.05). The RRs for the incidences of metabolically healthy and unhealthy obese (MHO and MUO, respectively) individuals in the high-GRS group were 0.94 (95% CI: 0.65-1.35) and 1.28 (95% CI: 1.00-1.63), respectively. CONCLUSION: High-GRS participants were more likely to be overweight/obese at baseline and follow-up, and this relationship exhibited a dose-response relationship. The GRS was also associated with MUO.


Assuntos
Obesidade/genética , Povo Asiático/genética , Índice de Massa Corporal , China , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Sobrepeso/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Estudos Prospectivos , Fatores de Risco
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