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1.
J Hazard Mater ; 470: 134214, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603908

RESUMO

Fe(II) regeneration is decisive for highly efficient H2O2-based Fenton-like processes, but the role of cobalt-containing reactive sites in promoting Fe(II) regeneration was overlooked. Herein, a single atom Co-N-C catalyst was employed in Fe(II)/H2O2 system to promote the degradation of diverse organic contaminants. The EPR and quenching experiments indicated Co-N-C significantly enhanced the generation of superoxide species, and accelerated hydroxyl radical generation for pollutant degradation. The electrochemical and surface composition analyses demonstrated the enhanced H2O2 activation and Fe(III)/Fe(II) recycling on the catalyst. Furthermore, in-situ Raman characterization with shell-isolated gold nanoparticles was employed to visualize the interfacial reactive intermediates and their time-resolved interaction. The accumulation of interfacial CoOOH* was confirmed when Co-N-C activated H2O2 alone, but it rapidly transformed into FeOOH* upon Fe(II) addition. Besides, the temporal variation of OOH* intermediates and the relative intensity of Co(III)-O and Co(IV)=O peaks depicted the dynamic interaction of reactive intermediates along the H2O2 consumption. With this basis, we proposed a mechanism of interfacial OOH* mediated Fe(II) regeneration, which overcame the kinetical limitation of Fe(II)/H2O2 system. Therefore, this study provided a primary effort to elucidate the overlooked role of interfacial CoOOH* in the Fenton-like processes, which may inspire the design of more efficient catalysts.

2.
Front Biosci (Landmark Ed) ; 28(9): 226, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37796688

RESUMO

BACKGROUND: In this study, we analyzed intestinal flora in an experimental mouse model of chronic kidney disease (CKD) and investigated whether oral supplementation with probiotic Lactobacillus rhamnosus GG could slow the decline in renal function and inflammatory status of mice with CKD. METHODS: We surgically induced chronic kidney disease in C57BL/6J male mice aged 8-9 weeks. We used dual-stage 5/6 nephrectomy for this, while the mock group underwent a mock procedure. The experimental (CKD mice) and mock group were administered a daily dose of 10 × 109 colony forming unit (CFU) of probiotic L. rhamnosus GG or 2 g of maltodextrin as a placebo by oral gavage, respectively, for 5 weeks. At the end of the experiment, the fecal samples of the mice were collected and prepared for intestinal microbial diversity analysis. We examined the serum chemistry and renal histology of the mice. RESULTS: Important serum and blood biomarkers were associated with the development of CKD, including increased serum concentrations of creatine, cystatin C, blood urea nitrogen (BUN), and a protein-interleukin-6 (denoted as IL-6), whereas decreased serum albumin concentration was also observed in the mice with CKD. The intestinal flora of the mice with CKD significantly declined in terms of diversity, richness, and homogeneity. The consumption of L. rhamnosus GG probiotic via oral gavage significantly decreased the serum concentration level present in creatinine and blood urea nitrogen. However, it increased albumin in the group with CKD. After probiotic treatment, serum IL-6 levels dropped considerably, and the kidney histopathology score in mice with CKD who were given L. rhamnosus GG improved. Moreover, supplementation with the probiotic significantly improved floral richness and lineage diversity in the mice with CKD.Conclusions: In this study, we found that probiotics significantly attenuated renal failure development, reduced serum levels of proinflammatory cytokine IL-6, and increased the abundance and lineage diversity of intestinal flora in mice with chronic kidney disease.


Assuntos
Lacticaseibacillus rhamnosus , Probióticos , Insuficiência Renal Crônica , Masculino , Animais , Camundongos , Interleucina-6 , Camundongos Endogâmicos C57BL , Rim/fisiologia , Insuficiência Renal Crônica/terapia , Probióticos/farmacologia , Probióticos/uso terapêutico , Biomarcadores
3.
Int J Ophthalmol ; 16(6): 947-954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37332557

RESUMO

AIM: To report outcomes of endoscopy-assisted vitrectomy (EAV) in patients with chronic hypotony following severe ocular trauma or vitrectomy. METHODS: This was a retrospective, noncomparative case series. Ciliary bodies were evaluated using ultrasound biomicroscopy pre-operatively and direct visualisation intraoperatively. All selected individuals (seven patients/seven eyes) underwent EAV. Removal of ciliary membrane and traction, gas/silicone oil tamponade (GT/SOT), and scleral buckling (SB) were performed in selected eyes. Outcome measurements mainly included intraocular pressure (IOP) and best-corrected visual acuity (BCVA). RESULTS: Seven eyes from 7 male aphakic patients with a mean age of 45 (range, 20-68)y were included in this study; the average follow-up time was 12 (9-15)mo. GT was performed in 2 eyes; membrane peeling (MP) and SOT in 2 eyes; and MP, SOT, and SB in 3 eyes. The mean pre- and post-operative IOP were 4.5 (range, 4.0±0.11 to 4.8±0.2) mm Hg and 9.9 (range, 5.6±0.17 to 12.1±0.2) mm Hg at 52wk (12mo), respectively. BCVA improved in six eyes; one eye still showed light perception, and no bulbi phthisis was observed. CONCLUSION: Endoscopy offers improved judgment and recognition and has an improved prognosis for chronic hypotony. Therefore, endoscopy can be an effective and promising operative technique for chronic traumatic hypotony management.

4.
Medicine (Baltimore) ; 101(37): e30212, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36123849

RESUMO

BACKGROUNDS: Epilepsy is a chronic encephalopathy caused by abnormal discharge of neurons in the brain, resulting in brain dysfunction. Cognitive impairment is one of the most common complications of epilepsy. The current treatment of epilepsy in the control of symptoms at the same time cause a lot of side effects, especially the aggravation of cognitive impairment. Many literatures have stated that the efficacy and safety of integrated Traditional Chinese and western medicine in the treatment of epilepsy with cognitive impairment is superior to that of western medicine alone. In this systematic review and meta-analysis, we intend to evaluate the clinical efficacy and safety of removing stasis and resolving phlegm in the treatment of epilepsy with cognitive impairment. OBJECTIVE: To systematically evaluate the clinical efficacy and safety of removing blood stasis and resolving phlegm in the treatment of epilepsy with cognitive impairment. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to conduct this systematic review. The Chinese Journal Full Text Database (CNKI), Wanfang Database, CQVIP Database (CQVIP), Cochrane Library, EMbase, and Pubmed were searched by computer, and randomized controlled studies on the efficacy of removing blood stasis and resolving phlegm in the treatment of epilepsy with cognitive disorders were included. Retrieval was carried out until January 2022, and relevant data were extracted for meta-analysis using Rev Man5.3 software. RESULTS: Fourteen randomized controlled studies with a total of 1198 patients were included, including 601 patients in the control group and 597 patients in the treatment group (experimental group). RESULTS: Meta-analysis results showed that compared with the treatment of epilepsy with cognitive impairment in the western anti-epileptic drugs group alone, the treatment of epilepsy with cognitive impairment combined with the method of removing blood stasis and resolving phlegm could significantly improve the clinical efficacy of epilepsy (OR = 3.41, 95% CI 2.39-4.88, P < .001). Improved the TCM symptom score (OR = 3.99, 95% CI 1.72-9.26, P < .001). Increased the EEG improvement rate (RR = 1.39, 95% CI 1.05-1.84, P = .02). Improved MOCA score and cognitive function (MD = 3.54, 95% CI 1.68-5.40, P < .001). Improved QOLIE-31 cognitive function score. Improved cognitive function (MD = 7.22, 95% CI 3.35-11.08, P < .001). Improved the incidence of adverse reactions (RR = 0.50, 95% CI 0.33-0.76, P = .001). CONCLUSION: Compared with the treatment of epilepsy with cognitive impairment by western anti-epileptic drugs alone, the treatment of epilepsy with cognitive impairment combined with the method of removing blood stasis and resolving phlegm is superior to the treatment of epilepsy with cognitive impairment by western anti-epileptic drugs alone.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Epilepsia , Disfunção Cognitiva/tratamento farmacológico , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Humanos , Medicina Tradicional Chinesa , Resultado do Tratamento
5.
RSC Adv ; 12(28): 17864-17872, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35765340

RESUMO

Singlet oxygen (1O2) is a promising reactive species for the selective degradation of organic pollutants. However, it is difficult to generate 1O2 from H2O2 activation with high efficiency and selectivity. In this work, a graphene-supported highly dispersed cobalt catalyst with abundant Co-N x active sites (Co-N-graphene) was synthesized for activating H2O2. The Co-N-graphene catalyzed H2O2 reaction system selectively catalyzed 1O2 production associated with the superoxide radical (O2˙-) as the critical intermediate, as proven by scavenger experiments, electron spin resonance (ESR) spin trapping and a kinetic solvent isotope effect study. This resulted in excellent degradation efficiency towards the model organic pollutant methylene blue (MB), with an outstanding pseudo-first-order kinetic rate constant of 0.432 min-1 (g Lcatalyst -1)-1 under optimal reaction conditions (C H2O2 = 400 mM, initial pH = 9). Furthermore, this Co-N-graphene catalyst enabled strong synergy with HCO3 - in accelerating MB degradation, whereas the scavenger experiment implied that the synergy herein differed significantly from the current Co2+-HCO3 - reaction system, in which contribution of O2˙- was only validated with a Co-N-graphene catalyst. Therefore, this work developed a novel catalyst for boosting 1O2 production from H2O2 activation and will extend the inventory of catalysts for advanced oxidation processes.

6.
iScience ; 24(12): 103401, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34841233

RESUMO

A microbial electrochemical system could potentially be applied as a biosynthesis platform by extracting wastewater energy while converting it to value-added chemicals. However, the unfavorable thermodynamics and sluggish kinetics of in vivo whole-cell cathodic catalysis largely limit product diversity and value. Herein, we convert the in vivo cathodic reaction to in vitro enzymatic catalysis and develop a microbe-enzyme hybrid bioelectrochemical system (BES), where microbes release the electricity from wastewater (anode) to power enzymatic catalysis (cathode). Three representative examples for the synthesis of pharmaceutically relevant compounds, including halofunctionalized oleic acid based on a cascade reaction, (4-chlorophenyl)-(pyridin-2-yl)-methanol based on electrochemical cofactor regeneration, and l-3,4-dihydroxyphenylalanine based on electrochemical reduction, were demonstrated. According to the techno-economic analysis, this system could deliver high system profit, opening an avenue to a potentially viable wastewater-to-profit process while shedding scientific light on hybrid BES mechanisms toward a sustainable reuse of wastewater.

7.
Trials ; 22(1): 657, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34565427

RESUMO

BACKGROUND: Infertility is a widespread global challenge. Currently, the most effective treatment strategy for infertility is in vitro fertilization (IVF), which is an assisted reproductive technique (ART). The use of IVF for assisted pregnancy dates back to the last 41 years when the first IVF baby was born. During IVF, many oocytes are obtained in an IVF cycle, and more than one embryo is formed. Subsequently, frozen-thawed embryo transfer (FET) is increasingly being used in IVF cycles for women in whom a fresh embryo transfer fails to result in a pregnancy, or in those who return for a second baby. However, the pregnancy success rates following FET treatment cycles are reportedly lower than in fresh embryo transfers. Therefore, recent related studies are increasing determining mechanisms of improving the sustained pregnancy rate of FET and reducing the rate of early abortion. The Gushen'antai pill (GSATP), which contains a mixture of 10 herbs, has been widely used in traditional Chinese medicine (TCM) as a pharmacological option to prevent miscarriage. However, randomized controlled trials (RCT) have never been conducted to provide high-level clinical evidence on the clinical efficacy of GSATP. The objective of this study is to investigate the effect of GSATP of hormone therapy (HT) FET cycles on pregnancy rate. METHODS: A total of 300 subjects aged between 18 and 40 years which prepared for HT cycle FET will be enrolled in the study. The patients were from five different hospitals, with 60 patients from each hospital. Patients were randomly divided into two groups, and medication was started on the day of endometrial transformation. After FET 28 days, B-ultrasound was done to determine whether to continue the medication. Baseline assessments were carried out before the trial and outcomes were collected 4, 6, 8, 10, and 12 weeks of each gestational cycle. DISCUSSION: Differences in ongoing pregnancy rate, clinical pregnancy rate, implantation rate, and threatened abortion rate between the two groups will be statistically analyzed. We can finally have an objective evaluation of the efficacy of the traditional Chinese medicine Gushen'antai pills. TRIAL REGISTRATION: ChiCTR1900026737 . Registered October 20, 2019.


Assuntos
Transferência Embrionária , Indução da Ovulação , Adolescente , Adulto , Feminino , Fertilização in vitro , Hormônios , Humanos , Estudos Multicêntricos como Assunto , Gravidez , Taxa de Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
8.
Nat Commun ; 11(1): 4087, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796822

RESUMO

By electronically wiring-up living cells with abiotic conductive surfaces, bioelectrochemical systems (BES) harvest energy and synthesize electric-/solar-chemicals with unmatched thermodynamic efficiency. However, the establishment of an efficient electronic interface between living cells and abiotic surfaces is hindered due to the requirement of extremely close contact and high interfacial area, which is quite challenging for cell and material engineering. Herein, we propose a new concept of a single cell electron collector, which is in-situ built with an interconnected intact conductive layer on and cross the individual cell membrane. The single cell electron collector forms intimate contact with the cellular electron transfer machinery and maximizes the interfacial area, achieving record-high interfacial electron transfer efficiency and BES performance. Thus, this single cell electron collector provides a superior tool to wire living cells with abiotic surfaces at the single-cell level and adds new dimensions for abiotic/biotic interface engineering.


Assuntos
Eletroquímica/métodos , Biofilmes/crescimento & desenvolvimento , Catálise , Eletrodos , Microscopia Eletroquímica de Varredura , Microscopia Eletrônica de Transmissão , Shewanella/metabolismo , Shewanella/ultraestrutura
9.
Am J Reprod Immunol ; 84(6): e13305, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32683731

RESUMO

The single nucleotide polymorphism T-1031C has shown to have an important role in the regulation and transcription efficiency of TNF-α gene. Yet, the relationship between TNF-α T-1031C gene polymorphism and the development of endometriosis (EM) still remains unclear. The aim of this meta-analysis was to summarize the effects of TNF-α T-1031C gene polymorphism and clarify their possible association with EM. A comprehensive literature search was performed using PubMed, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trials (up to August 10, 2019). A fixed- or random-effects model was employed according to the heterogeneity among studies. The log odds ratios and 95% confidence intervals (CIs) were estimated in the models of allele comparison (T vs C), homozygote comparison (TT vs CC) and (TC vs CC), dominant (TT vs TC + CC), hyperdominant (TT + CC vs TC), and recessive (TT + TC vs CC) to estimate the strength of the associations. A total of 7 case-control studies were included in this meta-analysis. Overall, significant associations between TNF-α T-1031C and EM were identified from (T vs C: log OR [95% CI] = 0.31 [-0.09, 0.71]; TT + CC vs TC: 0.27 [0.04, 0.50]; TC + CC vs TT: -0.83 [-1.19, -0.47]). On the other hand, no significant correlation was found in other gene models (TT vs TC: log OR [95% CI] = 0.89 [0.64, 1.13]; TT vs CC: 0.3 [-0.74, 1.36]; TT + TC vs CC: 0.17 [-0.81, 1.15]). In subgroup analyses by ethnicity or HWE P-value, there was a statistically significant association between TNF-α T-1031C polymorphisms and EM in the dominant model (TT vs TC + CC: log OR [95%] = -0.84 [-1.60, -0.09]) for the European population, and in hyperdominant model (TT + CC vs TC: log OR [95%] = 0.24 [0.001, 0.49]) for Asian population. To sum up, this meta-analysis showed that TNF-α T-1031C polymorphism was associated with EM susceptibility and has a protective effect in Asian and European populations.


Assuntos
Povo Asiático , Endometriose/genética , Genótipo , Fator de Necrose Tumoral alfa/genética , População Branca , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Polimorfismo Genético , Gravidez
10.
Front Genet ; 11: 376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411179

RESUMO

OBJECTIVE: This article is dedicated to finding important genes related to the prognosis of lung adenocarcinoma (LUAD), looking for a new gene that may affect tumor radiosensitivity, and conducting basic experiments to verify the relationship between this gene and the radiosensitivity of LUAD. METHODS: The gene expression profiles GSE32863, GSE33532, and GSE43458 were obtained from NCBI-GEO. GEO2R and a Venn diagram were used to identify upregulated genes. STRING and Cytoscape were applied to develop a protein-protein interaction network (PPI) and analyze the modules. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to process the GO and KEGG pathway analysis. The Kaplan Meier plotter and Gene Expression Profiling Interactive Analysis (GEPIA) were applied to get the significant prognostic information and differential expression between LUAD tissues and normal lung tissues. Western blotting and Q-PCR were used to detect the expression of PKMYT1 in tissues. Small interfering RNAs (siRNAs) were used to knockdown PKMYT1. The colony survival experiment was used to assess the effect of PMYT1 on the radiosensitivity of tumor cells. Cell cycle analysis was used to assess cell cycle distribution. RESULTS: We identified 14 genes (PKMYT1, TTK, CHEK1, CDC20, PTTG1, MCM2, CDC25C, MCM4, CCNB1, CDC45, MAD2L1, CCNB2, BUB1, and CCNA2) that are important for LUAD and may be potential therapeutic targets. We confirmed that PKMYT1 is highly expressed in LUAD and firstly demonstrated that artificially silencing the expression of PKMYT1 can abrogate IR-induced G2/M phase arrest and increase the sensitivity of cancer cells to radiation. CONCLUSION: In summary, we obtained 14 core genes related to the poor prognosis of LUAD via bioinformatical analysis. We identified that PKMYT1 was significantly upregulated in LUAD tissues and firstly demonstrated that knockdown of PKMYT1 can eliminate the radiation-induced G2/M arrest, resulting in a lower survival rate for cells receiving radiation therapy. Our findings suggested that PKMYT1 is a promising target to improve the radiosensitivity of LUAD.

11.
Bioresour Technol ; 288: 121499, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31128545

RESUMO

Electrode modifications with conductive and nanostructured polyaniline (PANI) were recognized as efficient approach to improve interaction between electrode surface and electrogenic bacteria for boosting the performance of microbial fuel cell (MFC). However, it still showed undesirable performance because of the challenge to control the orientation (such as vertical alignment) of PANI nanostructure for extracellular electron transfer (EET). In this work, vertically aligned polyaniline (VA-PANI) on carbon cloth electrode surface were prepared by in-situ polymerization method (simply tuning the ratio of tartaric acid (TA) dopant). Impressively, the VA-PANI greatly improved the EET due to the increased opportunity to connect with conductive proteins. Eventually, MFC equipped with the VA-PANI electrodes delivered a power output of 853 mW/m2, which greatly outperformed those electrodes modified with un-oriented PANI. This work provided the possibility to control the orientation of PANI for EET and promise to harvest energy from wastewater with MFC.


Assuntos
Fontes de Energia Bioelétrica , Nanofibras , Compostos de Anilina , Eletrodos
12.
Water Sci Technol ; 79(6): 1071-1080, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31070587

RESUMO

A bioelectrochemical sensing system (BES) based on electroactive bacteria (EAB) has been used as a new and promising tool for water toxicity assessment. However, most EAB can reduce heavy metals, which usually results in low toxicity response. Herein, a starvation pre-incubation strategy was developed which successfully avoided the metal reduction during the toxicity sensing period. By integrating this starvation pre-incubation procedure with the amperometric BES, a sensitive, robust and mediator-free biosensing method for heavy metal toxicity assessment was developed. Under the optimized conditions, the IC50 (half maximal inhibitory concentration) values for Cu2+, Ni2+, Cd2+, and Cr6+ obtained were 0.35, 3.49, 6.52, 2.48 mg L-1, respectively. The measurement with real water samples also suggested this method was reliable for practical application. This work demonstrates that it is feasible to use EAB for heavy metal toxicity assessment and provides a new tool for water toxicity warning.


Assuntos
Técnicas Biossensoriais , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Metais Pesados/análise , Água , Poluentes Químicos da Água/análise
13.
Anal Chem ; 91(8): 4939-4942, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30859817

RESUMO

An in vivo two-way redox cycling system based on whole-cell bidirectional electron transfer was developed and applied for independent duplexed electrochemical signal amplification. This duplexed signal amplification system was established by activating the bacterial "inwards" electron transfer at low electrode potential for oxidative cycling, while accomplishing the bacterial "outwards" electron transfer at high electrode potential for reductive cycling. Therefore, with this two-way bioredox cycling system, simultaneous and independent amplification of the electrochemical signals for oxidation and reduction was achieved. More impressively, by using this duplexed signal amplification system, ultrasensitive and simultaneous detection of two different warfare toxins of Pseudomonas aeruginosa was achieved (sensitivity was improved 302 and 579 times, respectively), which makes it possible for double-checking early diagnosis of the P. aeruginosa infections.


Assuntos
Eletroquímica/métodos , Oxirredução , Pseudomonas aeruginosa/química , Pseudomonas aeruginosa/metabolismo
14.
Zhongguo Zhong Yao Za Zhi ; 43(16): 3368-3375, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30200743

RESUMO

To explore the medication regularity of Tibetan medicine in the treatment of spleen and stomach diseases, analyze the potential drug targets and interactions of the prescriptions, and reveal the mechanism of Tibetan medicine in the treatment of spleen and stomach diseases. The prescriptions in Tibetan medicine for treatment of spleen and stomach diseases were collected, and Traditional Chinese Medicine Inheritance Support System (TCMISS) was used to analyze the association rules between the herbs and discover the core herbs and new prescriptions. The integrated pharmacology platform V1.0 software was used to construct "herb-compound-target" network and investigate the interactions between various herbs and related pathways of Tibetan medicine Wuwei Shiliu powder in the treatment of spleen and stomach diseases. Among the 216 prescriptions of Tibetan medicine in the treatment of spleen and stomach diseases, pomegranate seed was used at a highest frequency (118 times), followed by white cardamom (107 times) and comatose (107 times). 12 new prescriptions were evolved by using the association rules (support>=34%, confidence>=0.85). 5 242 related drug targets and 20 related pathways were obtained from classic formula Wuwei Shiliu Powder (FDR<0.01). It was proposed that Tibetan medicine treatment for spleen and stomach diseases was mainly based on proliferation of "stomach fire" and the main drugs were for regulating Qi-flowing for strengthening spleen. The mechanism may be associated with regulation of digestive juice secretion, proton pump, mitochondria, regulation of intestinal digestion and immunity, the body's immunity to microorganisms function and other multiple targets and pathways to achieve the joint intervention.


Assuntos
Mineração de Dados , Medicina Tradicional Tibetana , Gastropatias/tratamento farmacológico , Humanos , Baço/efeitos dos fármacos
15.
Ying Yong Sheng Tai Xue Bao ; 29(5): 1515-1522, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-29797884

RESUMO

Chinese fir plantation is an important part of the subtropical forests in southern China. It has a sustainable natural regeneration ability, which is the foundation of determining community succession direction and maintaining their large area. The main objective of this study was to investigate whether the seed pool was the main restricting factor for the natural regeneration of Chinese fir plantation. Mixed broad leaf-conifer forest and pure plantation of Chinese fir were selected to study the species composition, quantity and seasonal dynamics of all species and dominant species. The results showed that seeds from 21 species belonged to 13 families and 18 genera were collected in the mixed forest, while seeds from 19 species belonged to 12 families and 16 genera were collected from pure forest. Seed rain intensities of all species were 3797 and 3300 seeds·m-2 in mixed forest and pure plantation, respectively. The number of seeds from tree species was absolutely dominant in seed rain (mixed forest 89.1%, pure plantation 86.2%). The number of Chinese fir seeds was the largest, the intact seeds intensities were 825 and 345 seeds·m-2, respectively. The proportion of all types of seeds in both stands followed the order: the intact seeds > empty or rotten seeds > feeding seeds. The seed rain of both stands had significant seasonal dynamics, both reaching the peak in autumn. The seed rain mainly was intact seeds at the peak of seed-falling. Both mixed forest and pure plantation of Chinese fir had plenty of seeds. The results indicated that the seed rain is not the main factor that restricts natural regeneration in Chinese fir plantations.


Assuntos
Cunninghamia , Sementes , China , Estações do Ano , Árvores
16.
Anal Bioanal Chem ; 410(4): 1231-1236, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28965160

RESUMO

Toxicity assessment of water is of great important to the safety of human health and to social security because of more and more toxic compounds that are spilled into the aquatic environment. Therefore, the development of fast and reliable toxicity assessment methods is of great interest and attracts much attention. In this study, by using the electrochemical activity of Shewanella oneidensis MR-1 cells as the toxicity indicator, 3,5-dichlorophenol (DCP) as the model toxic compound, a new biosensor for water toxicity assessment was developed. Strikingly, the presence of DCP in the water significantly inhibited the maximum current output of the S. oneidensis MR-1 in a three-electrode system and also retarded the current evolution by the cells. Under the optimized conditions, the maximum current output of the biosensor was proportional to the concentration of DCP up to 30 mg/L. The half maximal inhibitory concentration of DCP determined by this biosensor is about 14.5 mg/L. Furthermore, simultaneous monitoring of the retarded time (Δt) for current generation allowed the identification of another biosensor signal in response to DCP which could be employed to verify the electrochemical result by dual confirmation. Thus, the present study has provided a reliable and promising approach for water quality assessment and risk warning of water toxicity.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas/instrumentação , Poluentes Químicos da Água/toxicidade , Clorofenóis/análise , Shewanella/metabolismo
17.
Oncotarget ; 8(61): 103393-103409, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29262570

RESUMO

Cardiac hypertrophy (CH) is an independent risk factor for cardiovascular diseases (CVDs). Mitigating or preventing CH is the most effective strategy for the treatment of CVDs. DanHong injection (DH) is a Chinese herbal medicine preparation (CHMP) widely used in clinical treatment of several CVDs in China. However, the direct targets and cellular mechanisms for these protective effects remain unclear. This study was designed to illustrate the direct targets of DH in protecting against CH and investigate CH molecular pathogenesis. A hypertrophic cell model was induced by endothelin-1 (ET-1) on human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). Real time cellular analysis (RTCA) cardio system and high content analysis (HCA) were used to detect the changes in contractile function, morphology and protein level of hypertrophic hiPS-CMs. Agonist and antagonist assay on receptors were performed using calcium mobilization high-throughput screening (HTS). DH significantly attenuated CH by modulating myocardial contractility, suppressing cell area enlargement and down-regulating ET-1-induced brain natriuretic peptide (BNP), actinin alpha 2 (ACTN2) and cardiac muscle troponin T (TNNT2) protein expression (P < 0.05). Endothelin receptor type B (ETBR) and angiotensin II receptor type 1 (AT1R) were DH direct targets, with IC50 value of 25.67 µL/mL and 1.10 µL/mL, respectively. Proteomics analysis showed that proteins involved in cell cycle inhibition, RNA processing, mitochondrial translation and cytoskeleton are significant regulated by DH treatment. These data revealed that ETBR and AT1R are DH direct targets on protecting against CH, providing a strategy to explore direct targets of CHMPs.

18.
Onco Targets Ther ; 10: 5605-5619, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200875

RESUMO

Non-small-cell lung cancer (NSCLC) is exceptionally deadly because the tumors lack sensitive early-stage diagnostic biomarkers and are resistant to radiation and chemotherapy. Here, we investigated the role and mechanism of Raf kinase inhibitory protein (RKIP) in NSCLC radioresistance. The clinical data showed that the RKIP expression level was generally lower in radioresistant NSCLC tissues than in radiosensitive tissues. Reduced RKIP expression was related to NSCLC radioresistance and poor prognosis. In vitro experiments showed that RKIP knockdown increased radioresistance and metastatic ability in NSCLC cell lines. Mechanistically, RKIP reduction activated the Shh signaling pathway by derepressing Smoothened (Smo) and initiating glioma-associated oncogene-1 (Gli1)-mediated transcription in NSCLC. In addition, the inappropriately activated Shh-Gli1 signaling pathway then enhanced cancer stem cell (CSC) expression in the cell lines. The increasing quantity of CSCs in the tumor ultimately promotes the radiation resistance of NSCLC. Together, these results suggest that RKIP plays a vital role in radiation response and metastasis in NSCLC. RKIP reduction enhances radioresistance by activating the Shh signaling pathway and initiating functional CSCs. This role makes it a promising therapeutic target for improving the efficacy of NSCLC radiation treatment.

19.
Anal Chim Acta ; 985: 148-154, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28864185

RESUMO

A novel whole-cell electrochemical sensor was developed and applied for sensitive amperometric detection of riboflavin. In this work, a whole-cell based riboflavin redox cycling system was characterized, in which electroactive bacteria Shewanella oneidensis MR-1 was employed as the biocatalyst to regenerate the reduced riboflavin after the electrode oxidation. This redox cycling system efficiently enhanced the electrochemical response of riboflavin and enabled a stable current output at poised electrode potential. Thus, a sensitive amperometric biosensing system for riboflavin detection was developed by integrating this whole-cell redox cycling system with the conventional riboflavin electrochemical sensor. Remarkably, this riboflavin biosensor exhibited high sensitivity (LOD = 0.85 ± 0.09 nM, S/N = 3), excellent selectivity and stability. Additionally, reliable analysis of real samples (food and pharmaceutical samples) by this biosensor was achieved. This work provided sensitive and practical tool for riboflavin detection, and demonstrated that the integration of electroactive bacteria and using its outwards electron transfer for redox cycling would be a powerful and promising strategy to improve the performance of electrochemical sensing system.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Riboflavina/análise , Shewanella/metabolismo , Eletrodos , Oxirredução
20.
Biosens Bioelectron ; 98: 338-344, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28709085

RESUMO

A bioelectrochemical sensing system based on a novel whole-cell redox reactivation/cycling module for ultrasensitive detection of pyocyanin (the biomarker of Pseudomonas aeruginosa infections) was developed. The electroactive bacteria mediated redox reactivation module was constructed using Shewanella oneidensis MR-1 cells as the bioelectro-catalyst and lactate as the electron donor. It could regenerate reductive pyocyanin from its oxidative state, which enabled pyocyanin molecule repeatedly registered by the electrode. Uniquely, with this redox reactivation module, the electrochemical response of pyocyanin was amplified about 405 times (1.3 µA/nM vs. 3.2nA/nM). Thus, an ultrasensitive bioelectrochemical sensing system for pyocyanin quantification was developed by integrating the pyocyanin reactivation module with conventional electrochemical detection system. Remarkably, with this developed biosensing system, an extremely low LOD of 47±1pM was reached. Additionally, this biosensing system showed excellent resistance to interferences from human fluids or bacterial contamination. This work provided a simple, ultrasensitive and robust tool for pyocyanin detection, and more importantly, demonstrated a new dimension for electrochemical signal amplification in biosensing.


Assuntos
Técnicas Biossensoriais , Infecções por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/isolamento & purificação , Piocianina/isolamento & purificação , Técnicas Eletroquímicas , Humanos , Oxirredução , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/patogenicidade , Piocianina/química
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