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1.
Clin Cancer Res ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526363

RESUMO

PURPOSE: Targeted therapy and immunotherapy are transforming the treatment approach for intrahepatic cholangiocarcinoma (ICC). However, little is known about the intertumor heterogeneity (ITH) of multifocal ICC and its impacts on patient response to these treatments. We aimed to characterize the immunogenomic and epigenomic heterogeneity of multifocal ICC to guide treatment decision making. EXPERIMENTAL DESIGN: We obtained 66 tumor samples from 16 patients with multifocal ICC and characterized the tumor and immune heterogeneity using whole-exome sequencing, bulk and single-cell RNA sequencing, methylation microarray, and multiplex immunostaining. Patients were divided into high- or low-ITH groups according to the median ITH index. Two independent cohorts were used to validate findings. Responses to anti-PD-1 therapy were assessed. RESULTS: Multifocal ICC presented considerable intertumor genomic, transcriptional, and epigenomic heterogeneity within a patient in high ITH group. The immune profile among multiple tumors within a patient was relatively less heterogeneous in high- or low-ITH group, and consistent responses of multiple tumors to anti-PD-1 immunotherapy were observed. Unsupervised clustering of immune markers identified one low and one high immune subtype, with higher immune cell infiltration, closer tumor-immune cell interactions, and upregulated IFN-signature expression in high-immune subtype. Determining expression levels of CD8B and ICOS facilitated this immune classification and prediction of patient prognosis. Finally, promoter DNA methylation contributed to different immune profiles of two subtypes by regulating immune-gene expression. CONCLUSIONS: There is comprehensive heterogeneity in the genome, transcriptome, and epigenome of multifocal ICC. On the basis of the less heterogeneous immune profile of ICC, we suggest an immune classification that stratifies patients' prognosis and may support personalized immunotherapy.

2.
BMJ Open ; 11(7): e048590, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226229

RESUMO

OBJECTIVE: The objective of this study was to evaluate the influence of secondhand smoke (SHS) exposure during childhood on type 2 diabetes mellitus, hypertension, hyperlipidaemia and coronary heart disease among Chinese non-smoking women. METHODS: In this cross-sectional study, the SHS exposure data in childhood were obtained using a questionnaire survey. Self-reported childhood SHS exposure was defined as the presence of at least one parent who smoked during childhood. RESULTS: Of the 6522 eligible participants, 2120 Chinese women who had never smoked were assessed. The prevalence of SHS exposure in the entire population was 28.1% (596). SHS exposure during childhood was not significant for the standard risk factors of type 2 diabetes mellitus (p=0.628) and hypertension (p=0.691). However, SHS was positively associated with hyperlipidaemia (p=0.037) after adjusting for age, obesity, education status, physical activity, alcohol consumption, current SHS exposure status, diabetes mellitus and hypertension. In addition, childhood SHS increased the occurrence of coronary heart disease (p=0.045) among non-smokers after further adjusting for hyperlipidaemia. CONCLUSION: SHS exposure during childhood is associated with prevalent hyperlipidaemia and coronary heart disease in adulthood among non-smoking Chinese women.


Assuntos
Doença das Coronárias , Diabetes Mellitus Tipo 2 , Hiperlipidemias , Poluição por Fumaça de Tabaco , Adulto , China/epidemiologia , Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Hiperlipidemias/epidemiologia , Hiperlipidemias/etiologia , Inquéritos e Questionários , Poluição por Fumaça de Tabaco/efeitos adversos
3.
J Ophthalmol ; 2021: 6613205, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239720

RESUMO

Purpose: Siderosis bulbi may occur as a result of retained intralenticular foreign bodies (ILFBs) that were missed during examination in patients with self-sealing wounds and without a significant decrease in visual acuity. This study aimed to explore the clinical characteristics and visual outcomes of ILFBs with self-sealing corneal penetrating wounds. Methods: Fifteen eyes of 15 patients with ILFBs and self-sealing corneal penetrating wounds, seen between October 2014 and September 2019, were retrospectively analyzed. Data regarding the patient demographics, clinical features, surgical procedure, and initial and final best-corrected visual acuity (BCVA) were analyzed. Results: All patients were male with a mean age of 41 years. The foreign bodies passed through the cornea, sometimes through the iris, through the anterior capsule, and finally localized in the lens. All ILFBs were pointed and metallic objects and were successfully removed with phacoemulsification and posterior chamber intraocular lens (IOL) implantation. Anterior capsule violation was found in three eyes, but no posterior capsule rupture was found. The IOL was placed in a capsule bag in all the cases. The BCVA ranged from 20/200 to 20/25 preoperatively and improved to between 20/32 and 20/20 at the last follow-up visit. The IOLs were well-centered. Apart from posterior capsule opacity in four eyes, no other postoperative complications were found. Conclusions: In patients with a pointed metallic ILFB and self-sealing corneal penetrating wounds (with or without cataracts), early diagnosis and removal of the metallic ILFB combined with lens removal and IOL implantation may avoid late complications and achieve good visual outcomes.

4.
J Gastroenterol Hepatol ; 36(9): 2531-2539, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33948991

RESUMO

BACKGROUND AND AIM: The evidences for use of postoperative antibiotics (POA) in hepatocellular carcinoma (HCC) patients who underwent hepatectomy are controversial. We aimed to explore the relationship between POA and hepatectomy-related infection in a hepatitis B virus (HBV)-related HCC population. METHODS: We retrospectively collected 934 HCC patients who underwent hepatectomy for curative intent from three tertiary hospitals in China. The incidences of postoperative infection including surgical site infection and remote site infection were recorded and calculated. Univariable and multivariable logistic regression analyses were performed to explore related factors of postoperative infection and POA. And the relationship between infection rates with different durations of POA was investigated. RESULTS: The overall infection rate was 8.2% (77/934), including 6.5% (61/934) of surgical site infection and 2.0% (19/934) of remote site infection. Multivariable analysis revealed that the administration of POA was negatively related with the incidence of postoperative infection significantly (odds ratio = 0.50, 95% confidence interval = 0.30 to 0.83; P = 0.008). Albumin-bilirubin score, Barcelona Clinic Liver Cancer (BCLC) stage and extent of hepatectomy were independently related to the POA. And 3-day regimen seemed to be the shortest duration of POA to gain the lowest incidence of postoperative infection. CONCLUSIONS: Postoperative antibiotic is necessary for HBV-related HCC patients to prevent postoperative infection, especially for those with higher albumin-bilirubin score, at BCLC stage B-C, or who underwent major hepatectomy. For HBV-related HCC patients, postoperative second-generation cephalosporins, or ceftriaxone for 3 days after surgery might be proper.

5.
Ann Surg Oncol ; 28(11): 6747-6757, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33751300

RESUMO

BACKGROUND: The aim of this work is to explore the impact of the number of sampling sites (NuSS) and sampling location on microvascular invasion (MVI) detection rate and long-term survival of hepatocellular carcinoma (HCC), and determine the minimum NuSS for sufficient MVI detection. PATIENTS AND METHODS: From January 2008 to March 2017, 1144 HCC patients who underwent hepatectomy were retrospectively enrolled. Associations between NuSS and MVI positive rates and overall survival were investigated. NuSS thresholds were determined by Chow test and confirmed prospectively in 305 patients from April 2017 to February 2019. In the prospective cohort, the distribution of MVI in different sampling locations and its prognostic effect was evaluated. RESULTS: MVI positive rates increased as NuSS increased, steadily reaching a plateau when NuSS reached a threshold. A threshold of four, six, eight, and eight sampling sites within paracancerous parenchyma ≤ 1 cm from tumor was required for detecting MVI in solitary tumors measuring 1.0-3.0, 3.1-4.9, and ≥ 5.0 cm and multiple tumors. Patients with adequate NuSS achieved longer survival than those with inadequate NuSS [hazard ratio (HR) = 0.75, P = 0.043]. For all MVI-positive patients, MVI could be detected positive in paracancerous parenchyma ≤ 1 cm from tumor. Patients with MVI positive in paracancerous parenchyma > 1 cm had higher recurrence risk than those with MVI positive only in parenchyma ≤ 1 cm (HR = 6.05, P < 0.001). CONCLUSIONS: Adequate NuSS is associated with higher MVI detection rate and better survival of HCC patients. We recommend four, six, eight, and eight as the cut-points for evaluating MVI sampling quality and patients' prognostic stratification in the subgroups of solitary tumors measuring 1.0-3.0 cm, 3.1-4.9 cm and ≥ 5.0 cm and multiple tumors, respectively.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Microvasos , Invasividade Neoplásica , Recidiva Local de Neoplasia/cirurgia , Estudos Prospectivos , Estudos Retrospectivos
6.
Exp Eye Res ; 205: 108506, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33609512

RESUMO

Glaucoma is a neuropathic disease that causes optic nerve damage, loss of retinal ganglion cells (RGCs), and visual field defects. Most glaucoma patients have no early signs or symptoms. Conventional pharmacological glaucoma medications and surgeries that focus on lowering intraocular pressure are not sufficient; RGCs continue to die, and the patient's vision continues to decline. Recent evidence has demonstrated that neuroprotective approaches could be a promising strategy for protecting against glaucoma. In the case of glaucoma, neuroprotection aims to prevent or slow down disease progression by mitigating RGCs death and optic nerve degeneration. Notably, new pharmacologic medications such as antiglaucomatous agents, antibiotics, dietary supplementation, novel neuroprotective molecules, neurotrophic factors, translational methods such as gene therapy and cell therapy, and electrical stimulation-based physiotherapy are emerging to attenuate the death of RGCs, or to make RGCs resilient to attacks. Understanding the roles of these interventions in RGC protection may offer benefits over traditional pharmacological medications and surgeries. In this review, we summarize the recent neuroprotective strategy for glaucoma, both in clinical trials and in laboratory research.


Assuntos
Glaucoma/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Doenças do Nervo Óptico/prevenção & controle , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Terapia Baseada em Transplante de Células e Tecidos/tendências , Terapia por Estimulação Elétrica/tendências , Terapia Genética/tendências , Humanos , Pressão Intraocular , Neuroproteção
7.
Int J Cardiol ; 325: 132-139, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-32966832

RESUMO

BACKGROUND: Inflammation is actively involved in the clinical manifestation of peripheral artery disease (PAD). Sonodynamic therapy (SDT), a novel non-invasive, plaque-based, macrophage-targeted anti-inflammatory regimen for atherosclerosis has the potential to improve walking performance by reducing plaque inflammation. METHODS: This phase-2, randomized, sham-controlled, double-blind clinical trial enrolled 32 participants with symptomatic femoropopliteal PAD. The primary outcome was the 30-day change in the target-to-background ratio (TBR) within the most diseased segment (MDS) of the femoropopliteal artery assessed through positron emission tomography/computed tomography (PET/CT). The secondary outcomes were changes in walking performance, limb perfusion, lesional morphology and quality of life measurements. RESULTS: The mean age was 64.7 years and 63% were male. Thirty-one completed follow-up. SDT significantly decreased the MDS TBR by 0.53 (95% CI, -0.70 to -0.36, P < 0.001) compared with control. Furthermore, SDT increased peak walking time by 118.6 s (95% CI, 74.3 to 163.0, P < 0.001), increased ankle-brachial index by 0.11 (95% CI, 0.07 to 0.14, P < 0.001), decreased lesional diameter and area stenosis by 7.2% (95% CI, -8.6 to -4.5, P < 0.001) and 9.6% (95% CI, -24.5 to -5.3, P = 0.005), respectively, and increased the walking speed score of the Walking Impairment Questionnaire by 16.1 (95% CI, 2.6 to 29.5, P = 0.021) and the physical functioning score of the 36-item Short-Form Health Survey by 10.0 (95% CI, 5.0 to 20.0, P = 0.003) compared with control. These improvements were maintained in the SDT group up to 6-month. CONCLUSIONS: SDT rapidly reduced plaque inflammation and improved walking performance among patients with symptomatic PAD. TRIAL REGISTRATION: Clinical Trials NCT03457662.


Assuntos
Doença Arterial Periférica , Feminino , Humanos , Inflamação , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Qualidade de Vida , Caminhada
8.
Life Sci ; 267: 118984, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383049

RESUMO

An increase in oxidative stress is an important pathological mechanism of heart injury induced by doxorubicin (DOX). Tranilast is an anti-allergy drug that has been shown to possess good antioxidant activity in previous studies. The overexpression and secretion of chymase by mast cells (MCs) increase the pathological overexpression of angiotensin II (Ang II), which plays a crucial role in myocardial hypertrophy and the deterioration of heart disease. The MC stabilizer tranilast (N-(3,4-dimethoxycinnamoyl) anthranilic acid; tran) prevents mast cells from degranulating, which may reduce DOX-induced Ang II synthesis. Therefore, in the present study, we hypothesized that tranilast will protect rats from DOX-induced myocardial damage via its antioxidant activity, thereby inhibiting Ang II expression. Thirty male Wistar rats were divided into three groups (n = 10 in each group) that received DOX, a combination of DOX and tranilast or saline (the control group) to test this hypothesis. Tranilast suppressed chymase expression, reduced Ang II levels and prevented the myocardial hypertrophy and the deterioration of heart function induced by DOX. Based on the findings of the present study, the suppression of chymase-dependent Ang-II production and the direct effect of tranilast on the inhibition of apoptosis and fibrosis because of its antioxidant stress capacity may contribute to the protective effect of tranilast against DOX-induced myocardial hypertrophy.


Assuntos
Angiotensina II/efeitos dos fármacos , Cardiomegalia/metabolismo , Doxorrubicina/efeitos adversos , ortoaminobenzoatos/farmacologia , Angiotensina II/biossíntese , Angiotensina II/metabolismo , Animais , Antioxidantes/farmacologia , Cardiomegalia/tratamento farmacológico , Doxorrubicina/farmacologia , Fibrose , Cardiopatias/etiologia , Masculino , Mastócitos/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , ortoaminobenzoatos/metabolismo
9.
Biomolecules ; 10(6)2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32466453

RESUMO

Fluostatins, benzofluorene-containing aromatic polyketides in the atypical angucycline family, conjugate into dimeric and even trimeric compounds in the post-biosynthesis. The formation of the C-C bond involves a non-enzymatic stereospecific coupling reaction. In this work, the unusual regio- and enantioselectivities were rationalized by density functional theory calculations with the M06-2X (SMD, water)/6-311 + G(d,p)//6-31G(d) method. These DFT calculations reproduce the lowest energy C1-(R)-C10'-(S) coupling pathway observed in a nonenzymatic reaction. Bonding of the reactive carbon atoms (C1 and C10') of the two reactant molecules maximizes the HOMO-LUMO interactions and Fukui function involving the highest occupied molecular orbital (HOMO) of nucleophile p-QM and lowest unoccupied molecular orbital (LUMO) of electrophile FST2- anion. In particular, the significant π-π stacking interactions of the low-energy pre-reaction state are retained in the lowest energy pathway for C-C coupling. The distortion/interaction-activation strain analysis indicates that the transition state (TScp-I) of the lowest energy pathway involves the highest stabilizing interactions and small distortion among all possible C-C coupling reactions. One of the two chiral centers generated in this step is lost upon aromatization of the phenol ring in the final difluostatin products. Thus, the π-π stacking interactions between the fluostatin 6-5-6 aromatic ring system play a critical role in the stereoselectivity of the nonenzymatic fluostatin conjugation.


Assuntos
Teoria da Densidade Funcional , Fluorenos/química , Policetídeos/química , Fluorenos/metabolismo , Estrutura Molecular , Policetídeos/metabolismo , Estereoisomerismo
10.
J Gastroenterol Hepatol ; 35(12): 2220-2228, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32246889

RESUMO

BACKGROUND AND AIM: Prognosis of infiltrative hepatocellular carcinoma (iHCC) is poor, and the treatments selection based on efficacy is unclear. We performed this multicenter study to compare the efficacy of hepatic resection and transarterial chemoembolization (TACE) in treating patients with iHCC. METHODS: We retrospectively analyzed the overall survivals (OS) in 319 patients with iHCC who were initially treated by hepatic resection (n = 133) or TACE (n = 186) at four tertiary centers. Fifty-eight patients in the TACE group were assessed as resectable and compared with the hepatic resection group in subgroup analysis. A propensity score matched (PSM) analysis was performed to reduce selection bias. Cox regression was performed to identify significant factors associated with OS. RESULTS: The median OS time was significantly longer in the hepatic resection group than that in the TACE group, before and after PSM (before PSM, 17.5 vs 7.3 months, P < 0.0001; after PSM, 14.0 vs 7.3 months, P < 0.0001). The multivariable analysis indicated TACE as a risk factor of OS (hazard ratio = 2.233, 95% confidence interval = 1.492 to 3.341, P < 0.0001), as well as portal venous tumor thrombosis grades 3-4 and alpha fetal protein (AFP) > 400 ng/mL. In the subgroup analysis, the better efficacy of hepatic resection over TACE persisted regardless of the grade of portal venous tumor thrombosis and the level of AFP. As for resectable patients, hepatic resection still showed significant survival benefit (before PSM, 17.5 vs 11.2 months, P = 0.0013; after PSM, 14.0 vs 10.9 months, P = 0.0304). CONCLUSION: Hepatic resection might be the better choice for patients with iHCC due to its better survival benefit than TACE.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Hepatectomia/métodos , Neoplasias Hepáticas/terapia , Adulto , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/mortalidade , Feminino , Hepatectomia/mortalidade , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
11.
Eur Radiol ; 30(6): 3473-3485, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32048035

RESUMO

OBJECTIVES: We used the status of microvascular invasion (MVI) at primary resection to help treatment selection for hepatitis B virus-positive (HBV+) recurrent hepatocellular carcinoma (rHCC) patients in Barcelona Clinic Liver Cancer (BCLC) stage B-C. METHODS: From 2009 to 2017, we enrolled 221 consecutive HBV+ rHCC patients at BCLC stage B-C who underwent re-resection (RR), radiofrequency ablation (RFA), or transarterial chemoembolization (TACE). Post recurrence survival (PRS) and overall survival (OS) were compared between RR/RFA and TACE according to MVI status. A one-to-one propensity score matching analysis was performed. RESULTS: For MVI(-) patients, the median PRS was 62.3 months for the RR/RFA group and 21.1 months for the TACE group (p = 0.039). The corresponding OS was 71.4 months and 26.6 months, respectively (p = 0.010). For MVI(+) patients, the median PRS in the RR/RFA group and TACE group was 14.7 months and 10.1 months (p = 0.115). The corresponding OS was 23.4 months and 16.4 months, respectively (p = 0.067). After matching, the dominance of RR/RFA over TACE remained in MVI(-) patients for both PRS (62.3 months vs 15.3 months, p = 0.019) and OS (98.1 months vs 33.4 months, p = 0.046). No significant difference was found in MVI(+) patients for either PRS (14.7 months vs 11.8 months, p = 0.593) or OS (23.4 months vs 28.1 months, p = 0.662). CONCLUSIONS: MVI status definitely helps select treatment options in HBV+ rHCC patients. For MVI(-) patients, RR/RFA provided better survival than TACE while for MVI(+) patients, TACE shared similar survival outcomes. KEY POINTS: • This study aimed at the determination of the optimal treatment options (ablation /resection vs TACE) in case of recurrent HBV-related HCC. • It showed that MVI status, established at primary resection of HCC, was a powerful marker for selecting the best treatment option in these patients. • In MVI(-) patients, RR/RFA achieved a better survival than TACE. In MVI(+) patients, TACE shared similar survival.


Assuntos
Carcinoma Hepatocelular/terapia , Ablação por Cateter , Quimioembolização Terapêutica , Hepatectomia , Hepatite B Crônica/complicações , Neoplasias Hepáticas/terapia , Microvasos/patologia , Recidiva Local de Neoplasia/terapia , Adulto , Idoso , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Vírus da Hepatite B , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Seleção de Pacientes , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
12.
ACS Appl Mater Interfaces ; 9(39): 34243-34255, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28901126

RESUMO

It is widely recognized that constructing multiple interface structures for enhanced interface polarization is beneficial to microwave absorption. Here, we report our work of achieving excellent microwave-absorption performance and controlling better-defined interfaces in vertically stacked two-dimensional (2D) MoS2 with other dimensional building blocks. The optimal reflection loss and effective absorbing bandwidth (reflection loss <-10 dB) of several mixed-dimensional van der Waals heterostructures are as follows: (i) for 2-0 type (2D MoS2/zero-dimensional Ni nanoparticles), -19.7 dB and 2.92 GHz; (ii) for 2-1 type (2D MoS2/one-dimensional carbon nanotubes), -47.9 dB and 5.60 GHz; and (iii) for 2-3 type (2D MoS2/three-dimensional carbon layers), -69.2 dB and 4.88 GHz. As a result, by selected synthesis of different types of microstructures, we can regulate and control microwave-absorption properties in MoS2 mixed-dimensional van der Waals heterostructures. In addition, attributing to the better-defined interfaces generated in mixed-dimensional van der Waals heterostructures, we found an alternative strategy to improve microwave attenuation properties of 2-0, 2-1, and 2-3 samples by controlling interfacial contacts. The results indicate that mixed-dimensional van der Waals heterostructures provide a new stage for the next generation of microwave-absorbing materials.

13.
Sci Rep ; 7(1): 11891, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28928375

RESUMO

The development of efficient, universal and inexpensive electrocatalysts for hydrogen evolution reaction (HER) is central to the area of sustainable energy conversion. Considering the Co-based sulfides/phosphides have the same catalytic mechanism with the hydrogenases occurring in nature. Here, a new catalyst based on Co3S4/CoP hybrid that is comprised entirely cheap and earthabundant elements, was first synthesized via a two-step method, the Co(CO3)0.5(OH)·0.11H2O precursor was prepared by a hydrothermal method, followed by phosphidation and sulphidation under Ar atmosphere simultaneously. The resulting Co3S4/CoP hybrid material possessed porous core-shell structure with a homogeneous element distribution and large electroactive surface area (~21.04 mF cm-2). More importantly, the nanostructured Co3S4/CoP electrode exhibits excellent HER properties in acid medium with a low onset overpotential of 34 mV, a small Tafel slope of 45 mV dec-1, as well as a large exchange current density of 150 µA cm-2. These results obtained in this study indicate that the Co3S4/CoP hybrid nanorod is promising replacement to the Pt-based catalysts for H2 production. Moreover, the synthetic method presented in this work can provide an efficient way to synthesis other nanocomposites.

14.
Chem Commun (Camb) ; 53(23): 3357-3360, 2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28261715

RESUMO

Novel Cu-In-S quantum dots (CIS QDs), which exhibit interesting aggregation-induced emission (AIE) properties, were successfully prepared via a hydrothermal method. When the solvent was changed from water to 90 vol% DMSO, the photoluminescence intensity of the as-prepared CIS QDs was enhanced about 126-fold.

15.
Appl Environ Microbiol ; 83(8)2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28258138

RESUMO

A single liter of water contains hundreds, if not thousands, of bacterial and archaeal species, each of which typically makes up a very small fraction of the total microbial community (<0.1%), the so-called "rare biosphere." How often, and via what mechanisms, e.g., clonal amplification versus horizontal gene transfer, the rare taxa and genes contribute to microbial community response to environmental perturbations represent important unanswered questions toward better understanding the value and modeling of microbial diversity. We tested whether rare species frequently responded to changing environmental conditions by establishing 20-liter planktonic mesocosms with water from Lake Lanier (Georgia, USA) and perturbing them with organic compounds that are rarely detected in the lake, including 2,4-dichlorophenoxyacetic acid (2,4-D), 4-nitrophenol (4-NP), and caffeine. The populations of the degraders of these compounds were initially below the detection limit of quantitative PCR (qPCR) or metagenomic sequencing methods, but they increased substantially in abundance after perturbation. Sequencing of several degraders (isolates) and time-series metagenomic data sets revealed distinct cooccurring alleles of degradation genes, frequently carried on transmissible plasmids, especially for the 2,4-D mesocosms, and distinct species dominating the post-enrichment microbial communities from each replicated mesocosm. This diversity of species and genes also underlies distinct degradation profiles among replicated mesocosms. Collectively, these results supported the hypothesis that the rare biosphere can serve as a genetic reservoir, which can be frequently missed by metagenomics but enables community response to changing environmental conditions caused by organic pollutants, and they provided insights into the size of the pool of rare genes and species.IMPORTANCE A single liter of water or gram of soil contains hundreds of low-abundance bacterial and archaeal species, the so called rare biosphere. The value of this astonishing biodiversity for ecosystem functioning remains poorly understood, primarily due to the fact that microbial community analysis frequently focuses on abundant organisms. Using a combination of culture-dependent and culture-independent (metagenomics) techniques, we showed that rare taxa and genes commonly contribute to the microbial community response to organic pollutants. Our findings should have implications for future studies that aim to study the role of rare species in environmental processes, including environmental bioremediation efforts of oil spills or other contaminants.


Assuntos
Biodiversidade , Ecossistema , Água Doce/microbiologia , Consórcios Microbianos/fisiologia , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacologia , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Archaea/classificação , Archaea/genética , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Cafeína/metabolismo , Cafeína/farmacologia , Georgia , Lagos/microbiologia , Metagenômica , Consórcios Microbianos/efeitos dos fármacos , Consórcios Microbianos/genética , Nitrofenóis/metabolismo , Nitrofenóis/farmacologia , Filogenia , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real , Poluentes Químicos da Água/química
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