Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-31993906

RESUMO

Aerobic CH4 oxidation coupled to denitrification (AME-D) can not only mitigate the emission of greenhouse gas (e.g., CH4) to the atmosphere, but also reduce NO3- and/or NO2- and alleviate nitrogen pollution. The effects of O2 tension on the community and functional gene expression of methanotrophs and denitrifiers were investigated in this study. Although higher CH4 oxidation occurred in the AME-D system with an initial O2 concentration of 21% (i.e., the O2-sufficient condition), more NO3--N was removed at the initial O2 concentration of 10% (i.e., the O2-limited environment). Type I methanotrophs, including Methylocaldum, Methylobacter, Methylococcus, Methylomonas, and Methylomicrobium, and type II methanotrophs, including Methylocystis and Methylosinus, dominated in the AME-D systems. Compared with type II methanotrophs, type I methanotrophs were more abundant in the AME-D systems. Proteobacteria and Actinobacteria were the main denitrifiers in the AME-D systems, and their compositions varied with the O2 tension. Quantitative PCR of the pmoA, nirS, and 16S rRNA genes showed that methanotrophs and denitrifiers were the main microorganisms in the AME-D systems, accounting for 46.4% and 24.1% in the O2-limited environment, respectively. However, the relative transcripts of the functional genes including pmoA, mmoX, nirK, nirS, and norZ were all less than 1%, especially the functional genes involved in denitrification under the O2-sufficient condition, likely due to the majority of the denitrifiers being dormant or even nonviable. These findings indicated that an optimal O2 concentration should be used to optimize the activity and functional gene expression of aerobic methanotrophs and denitrifiers in AME-D systems.

2.
Environ Pollut ; : 113676, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31818614

RESUMO

CH4 oxidation in landfill cover soils plays a significant role in mitigating CH4 release to the atmosphere. Oxygen availability and the presence of co-contaminants are potentially important factors affecting CH4 oxidation rate and the fate of CH4-derived carbon. In this study, microbial populations that oxidize CH4 and the subsequent conversion of CH4-derived carbon into CO2, soil organic C and biomass C were investigated in landfill cover soils at two O2 tensions, i.e., O2 concentrations of 21% ("sufficient") and 2.5% ("limited") with and without toluene. CH4-derived carbon was primarily converted into CO2 and soil organic C in the landfill cover soils, accounting for more than 80% of CH4 oxidized. Under the O2-sufficient condition, 52.9%-59.6% of CH4-derived carbon was converted into CO2 (CECO2-C), and 29.1%-39.3% was converted into soil organic C (CEorganic-C). A higher CEorganic-C and lower CECO2-C occurred in the O2-limited environment, relative to the O2-sufficient condition. With the addition of toluene, the carbon conversion efficiency of CH4 into biomass C and organic C increased slightly, especially in the O2-limited environment. A more complex microbial network was involved in CH4 assimilation in the O2-limited environment than under the O2-sufficient condition. DNA-based stable isotope probing of the community with 13CH4 revealed that Methylocaldum and Methylosarcina had a higher relative growth rate than other type I methanotrophs in the landfill cover soils, especially at the low O2 concentration, while Methylosinus was more abundant in the treatment with both the high O2 concentration and toluene. These results indicated that O2-limited environments could prompt more CH4-derived carbon to be deposited into soils in the form of biomass C and organic C, thereby enhancing the contribution of CH4-derived carbon to soil community biomass and functionality of landfill cover soils (i.e. reduction of CO2 emission).

3.
Arch Pharm (Weinheim) ; 352(8): e1900024, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31338897

RESUMO

A series of novel 3-(thiophen-2-ylthio)pyridine derivatives as insulin-like growth factor 1 receptor (IGF-1R) inhibitors was designed and synthesized. IGF-1R kinase inhibitory activities and cytotoxicities against HepG2 and WSU-DLCL2 cell lines were tested. For all of these compounds, potent cancer cell proliferation inhibitory activities were observed, but not through the inhibition of IGR-1R. Selected compounds were further screened against various kinases. Typical compound 22 (50% inhibitory concentration [IC50 ] values, HepG2: 2.98 ± 1.11 µM and WSU-DLCL2: 4.34 ± 0.84 µM) exhibited good inhibitory activities against fibroblast growth factor receptor-2 (FGFR2), FGFR3, epidermal growth factor receptor, Janus kinase, and RON (receptor originated from Nantes), with IC50 values ranging from 2.14 to 12.20 µM. Additionally, the cell-cycle analysis showed that compound 22 could arrest HepG2 cells in the G1/G0 phase. Taken together, all the experiments confirmed that the compounds in this series were multitarget anticancer agents worth further optimizing.

4.
Waste Manag ; 91: 128-138, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203934

RESUMO

Gaseous emissions from municipal solid waste (MSW) disposal plants pose serious odor pollution and health risks. In this study, the emission of volatile organic compounds and carbon disulfide was compared in the main processing units of three disposal methods, i.e., landfilling, eco-mechanical biological treatment (EMBT) and anaerobic fermentation in a MSW disposal plant. Among the detected volatile compounds (VCs), the top ten odor compounds were methanethiol, dimethyl sulfide, dimethyl disulfide, carbon disulfide, styrene, m-xylene, 4-ethyltoluene, ethylbenzene, 2-hexyl ketone and n-hexane in the MSW disposal plant. Sulfur compounds were the main source of odor at the majority of sampling sites, and aromatic compounds were the dominant odor substrates at the tipping unit and sorting system of EMBT, while 2-hexanone was the major odor substrate at the tipping unit (AT) and sorting system (AS) of anaerobic fermentation and the landfill working surface. At AS and AT, the lifetime cancer risk values for 1,2-dichloroethane and trichloroethylene exceeded the carcinogenic risk value (>1.0E-04), and the hazard index values of naphthalene, trichloroethylene and acrolein all exceeded the acceptable level (>1). Therefore, special attention should be paid to VC emissions from MSW disposal facilities, and protection measures should be adopted for on-site workers to minimize health risks.


Assuntos
Poluentes Atmosféricos , Eliminação de Resíduos , Humanos , Odorantes , Resíduos Sólidos , Instalações de Eliminação de Resíduos
5.
Oncol Rep ; 41(1): 341-350, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30542705

RESUMO

The ß2­adrenergic receptor (ß2­AR, encoded by the ADRB2 gene) is a member of the G­protein­coupled receptor superfamily that can be stimulated by catecholamines. Studies in vivo and in vitro have confirmed that ß­blockers (ß­AR antagonists) exert antitumor effects on various tumors. Furthermore, ADRB2 single­nucleotide polymorphisms (SNPs) have been identified to alter the expression and conformation of ß2­AR, which may alter the ß­blocker drug response. The aim of the present study was to investigate the effect of ß­blockers on triple­negative breast cancer cells and determine whether ADRB2 SNPs affect the response to ß­blocker drugs. Propranolol and ICI 118,551 significantly inhibited the viability of MDA­MB­231 cells, arrested cell cycle progression at G0/G1 and S phase and induced cell apoptosis. Western blot analysis indicated that the phosphorylation levels of extracellular­signal­regulated kinase (ERK)1/2 and the expression levels of cyclo­oxygenase 2 (COX­2) were significantly decreased following ß­blocker treatment. Four haplotypes, which comprised ADRB2 SNPs rs1042713 and rs1042714, were transfected into 293 cells. After 24 and 48 h of transfection, ADRB2 mRNA expression was significantly decreased in mutant groups compared with the wild­type group. The ADRB2 SNPs exerted no effect on cell viability, but did affect the drug response of ICI 118,551. Furthermore, ADRB2 SNPs also affected the regulatory function of ICI 118,551 on the ERK/COX­2 signaling pathway. Collectively, propranolol and ICI 118,551 inhibited the viability of MDA­MB­231 cells by downregulating the ERK/COX­2 signaling pathway and inducing apoptosis. The results of the present study indicated that SNPs rs1042713 and rs1042714 of ADRB2 affected the response to ICI 118,551, and the underlying molecular mechanism was elucidated.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Receptores Adrenérgicos beta 2/genética , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Fosforilação/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Propanolaminas/farmacologia , Propanolaminas/uso terapêutico , Propranolol/farmacologia , Propranolol/uso terapêutico , Receptores Adrenérgicos beta 2/metabolismo , Neoplasias de Mama Triplo Negativas/genética
6.
Chin Med J (Engl) ; 131(23): 2817-2826, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30511684

RESUMO

Background: Glucocorticoid (GC) is the first-line therapy for asthma, but some asthmatics are insensitive to it. Glucocorticoid-induced transcript 1 gene (GLCCI1) is reported to be associated with GCs efficiency in asthmatics, while its exact mechanism remains unknown. Methods: A total of 30 asthmatic patients received fluticasone propionate for 12 weeks. Forced expiratory volume in 1 s (FEV1) and GLCCI1 expression were detected. Asthma model was constructed in wild-type and GLCCI1 knockout (GLCCI1-/-) mice. Glucocorticoid receptor (GR) and mitogen-activated protein kinase phosphatase 1 (MKP-1) expression were detected by polymerase chain reaction and Western blotting (WB). The phosphorylation of p38 mitogen-activated protein kinase (MAPK) was also detected by WB. Results: In asthmatic patients, the change of FEV1 was well positively correlated with change of GLCCI1 expression (r = 0.430, P = 0.022). In animal experiment, GR and MKP-1 mRNA levels were significantly decreased in asthmatic mice than in control mice (wild-type: GR: 0.769 vs. 1.000, P = 0.022; MKP-1: 0.493 vs. 1.000, P < 0.001. GLCCI1-/-: GR: 0.629 vs. 1.645, P < 0.001; MKP-1: 0.377 vs. 2.146, P < 0.001). Hydroprednisone treatment significantly increased GR and MKP-1 mRNA expression levels than in asthmatic groups; however, GLCCI1-/- asthmatic mice had less improvement (wild-type: GR: 1.517 vs. 0.769, P = 0.023; MKP-1: 1.036 vs. 0.493, P = 0.003. GLCCI1-/-: GR: 0.846 vs. 0.629, P = 0.116; MKP-1: 0.475 vs. 0.377, P = 0.388). GLCCI1-/- asthmatic mice had more obvious phosphorylation of p38 MAPK than wild-type asthmatic mice (9.060 vs. 3.484, P < 0.001). It was still higher even though after hydroprednisone treatment (6.440 vs. 2.630, P < 0.001). Conclusions: GLCCI1 deficiency in asthmatic mice inhibits the activation of GR and MKP-1 and leads to more obvious phosphorylation of p38 MAPK, leading to a decremental sensitivity to GCs. Trial Registration: ChiCTR.org.cn, ChiCTR-RCC-13003634; http://www.chictr.org.cn/showproj.aspx?proj=5926.


Assuntos
Asma/tratamento farmacológico , Asma/metabolismo , Glucocorticoides/uso terapêutico , Receptores de Glucocorticoides/deficiência , Receptores de Glucocorticoides/metabolismo , Animais , Fosfatase 1 de Especificidade Dupla/genética , Fosfatase 1 de Especificidade Dupla/metabolismo , Volume Expiratório Forçado/genética , Volume Expiratório Forçado/fisiologia , Camundongos , Camundongos Knockout , Fosforilação/genética , Fosforilação/fisiologia , Receptores de Glucocorticoides/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Waste Manag ; 76: 383-393, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29636216

RESUMO

Volatile sulfur compounds (VSCs) are not only the main source of malodor in anaerobic treatment of organic waste, but also pose a threat to human health. In this study, VSCs production and microbial community was investigated during the anaerobic degradation of fish and pork waste. The results showed that after the operation of 245 days, 94.5% and 76.2% of sulfur compounds in the fish and pork waste was converted into VSCs. Among the detected VSCs including H2S, carbon disulfide, methanethiol, ethanethiol, dimethyl sulfide, dimethyl disulfide and dimethyl trisulfide, methanethiol was the major component with the maximum concentration of 4.54% and 3.28% in the fish and pork waste, respectively. The conversion of sulfur compounds including total sulfur, SO42--S, S2-, methionine and cysteine followed the first-order kinetics. Miseq sequencing analysis showed that Acinetobacter, Clostridium, Proteus, Thiobacillus, Hyphomicrobium and Pseudomonas were the main known sulfur-metabolizing microorganisms in the fish and pork waste. The C/N value had most significant influence on the microbial community in the fish and pork waste. A main conversion of sulfur compounds with CH3SH as the key intermediate was firstly hypothesized during the anaerobic degradation of fish and pork waste. These findings are helpful to understand the conversion of sulfur compounds and to develop techniques to control ordor pollution in the anaerobic treatment of organic waste.


Assuntos
Carne Vermelha , Compostos de Enxofre/química , Gerenciamento de Resíduos , Animais , Peixes , Compostos de Sulfidrila , Enxofre , Suínos
8.
Environ Sci Pollut Res Int ; 25(17): 16816-16824, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29616477

RESUMO

Methanotrophs not only oxidize CH4, but also can oxidize a relatively broad range of other substrates, including trichloroethylene, alkanes, alkenes, and aromatic compounds. In this study, Methylosinus sporium was used as a model organism to characterize toluene metabolism by methanotrophs. Reverse transcription quantitative PCR analysis showed that toluene enhanced the mmoX expression of M. sporium. When the toluene concentration was below 2000 mg m-3, the kinetics of toluene metabolism by M. sporium conformed to the Michaelis-Menten equation (Vmax = 0.238 g gdry weight-1 h-1, K m = 545.2 mg m-3). The use of a solid-phase extraction technique followed by a gas chromatography-mass spectrometry analysis and molecular docking calculation showed that toluene was likely to primarily bind the di-iron center structural region of soluble methane monooxygenase (sMMO) hydroxylase and then be oxidized to o-cresol. Although M. sporium oxidized toluene, it did not incorporate toluene into its biomass. The coexistence of toluene and CH4 could influence CH4 oxidation, the growth of methanotrophs, and the distribution of CH4-derived carbon, which were related to the ratio of the toluene concentration to biomass. These results would be helpful to understand the metabolism of CH4 and non-methane volatile organic compounds in the environment.


Assuntos
Metano/metabolismo , Oxigenases/metabolismo , Tolueno/metabolismo , Tricloroetileno/metabolismo , Biomassa , Cinética , Metano/química , Simulação de Acoplamento Molecular , Oxirredução , Oxigenases/química , Tolueno/química , Tricloroetileno/química
9.
Environ Sci Pollut Res Int ; 24(30): 23992-24001, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28879507

RESUMO

Volatile sulfur compounds are the main odorants at landfills. In this study, methanethiol (CH3SH) was chosen as a typical volatile organic sulfur compound, and its generation potential was investigated during the anaerobic degradation of the organic fractions of municipal solid waste (MSW) including rice, flour food, vegetable, fish and pork, paper, cellulose textile, and yard wastes. Among the experimental wastes, gas generation was the highest in the fish and pork waste with a high CH3SH concentration of up to 2.5% (v/v). Sulfur reduction in the solid phase was mostly converted into gaseous sulfur compounds. During the whole experiment, the cumulative CH3SH generation from the fish and pork waste was 0.139 L kgdw-1, which was about 2 and 6 orders of magnitude higher than that from the other experimental wastes. The ratio of CH3SH-S to TS reduction was 31.56% in the fish and pork waste. These results would be helpful to understand the generation of volatile sulfur compounds during the anaerobic degradation of MSW and develop techniques to control odor pollution at landfills.


Assuntos
Compostos de Sulfidrila/análise , Compostos de Enxofre/química , Animais , Gases , Odorantes , Resíduos Sólidos , Compostos de Sulfidrila/química , Suínos , Instalações de Eliminação de Resíduos
10.
Waste Manag ; 69: 289-297, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28803765

RESUMO

The accumulation of extracellular polymeric substance (EPS) is speculated to be related with the decrease of CH4 oxidation rate after a peak in long-term laboratory landfill covers and biofilters. However, few data have been reported about EPS production of methanotrophs and its feedback effects on methanotrophic activity. In this study, Methylosinus sporium was used asa model methanotroph to investigate EPS production and its influencing factors during CH4 oxidation. The results showed that methanotrophs could secret EPS into the habits during CH4 oxidation and had a negative feedback effect on CH4 oxidation. The EPS amount fitted well with the CH4 oxidation activity with the exponential model. The environmental factors such as pH, temperature, CH4, O2, NO3--N and NH4+-N could affect the EPS production of methanotrophs. When pH, temperature, CH4, O2 and N concentrations (including NO3--N and NH4+-N) were 6.5-7.5, 30-40°C, 10-15%, 10% and 20-140mgL-1, respectively, the high cell growth rate and CH4 oxidation activity of Methylosinus sporium occurred in the media with the low EPS production, which was beneficial to sustainable and efficient CH4 oxidation. In practice, O2-limited condition such as the O2 concentration of 10% might be a good way to control EPS production and enhance CH4 oxidation to mitigate CH4 emission from landfills.


Assuntos
Metano/metabolismo , Microbiologia do Solo , Instalações de Eliminação de Resíduos , Metano/análise , Nitratos/química , Oxirredução , Polímeros
11.
J Biosci Bioeng ; 123(4): 466-473, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27939869

RESUMO

Ammonium (NH4+) is not only nitrogen source that can support methanotrophic growth, but also it can inhibit methane (CH4) oxidation by competing with CH4 for the active site of methane monooxygenase. NH4+ conversion and its feedback effect on the growth and activity of methanotrophs were evaluated with Methylosinus sporium used as a model methanotroph. Nitrogen sources could affect the CH4-derived carbon distribution, which varied with incubation time and nitrogen concentrations. More CH4-derived carbon was incorporated into biomass in the media with NH4+-N, compared to nitrate-nitrogen (NO3--N), as sole nitrogen source at the nitrogen concentrations of 10-18 mmol L-1. Although ammonia (NH3) oxidation activity of methanotrophs was considerably lower, only accounting for 0.01-0.06% of CH4 oxidation activity in the experimental cultures, NH4+ conversion could lead to the pH decrease and toxic intermediates accumulation in the their habits. Compared with NH4+, nitrite (NO2-) accumulation in the NH4+ conversion of methanotroph had stronger inhibition on its activity, especially the joint inhibition of NO2- accumulation and the pH decrease during the NH4+-N conversion. These results suggested that more attention should be paid to the feedback effects of NH4+ conversion by methanotrophs to understand effects of NH4+ on CH4 oxidation in the environments.


Assuntos
Compostos de Amônio/metabolismo , Retroalimentação Fisiológica , Metano/metabolismo , Methylosinus/metabolismo , Amônia/metabolismo , Ligação Competitiva , Biomassa , Domínio Catalítico , Concentração de Íons de Hidrogênio , Methylosinus/enzimologia , Methylosinus/crescimento & desenvolvimento , Nitratos/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Oxirredução , Oxigenases/química , Oxigenases/metabolismo
12.
Ying Yong Sheng Tai Xue Bao ; 28(6): 1786-1792, 2017 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-29745139

RESUMO

Warming-induced decrease in seasonal snow cover has a great potential to affect soil nitrogen cycle in alpine cold forest ecosystems. In this study, a wooden-shelter method was used to remove the snow accumulation. Soil nitrogen pools and mineralization rates in the snow removal and control plots were measured synchronously in three critical periods (early snow cover, deep snow cover and snow cover melting) in a subalpine spruce forest of western Sichuan, China. Seasonal snow cover kept soil from cold air temperature. Snow removal decreased average and minimum soil temperatures (5 cm) by 0.33 and 1.17 ℃, respectively. In addition, snow removal caused a positive effect on soil frost depth and freeze-thaw cycle. There was a significant dynamic in soil labile nitrogen pool among different periods. Snow removal on average increased NH4+-N, NO3--N and dissolved organic nitrogen (DON) contents by 38.6%, 23.5% and 57.3%, respectively, over the winter. Moreover, snow removal increased soil net nitrification and mineralization rates in the snow co-ver melting period. Overall, warming-induced decrease in snow cover could stimulate winter soil nitrogen cycle of subalpine forests.


Assuntos
Nitrogênio , Neve , Solo , China , Florestas , Estações do Ano
13.
Ying Yong Sheng Tai Xue Bao ; 28(6): 2047-2054, 2017 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-29745170

RESUMO

Methane bio-oxidation plays an important role in the global methane balance and greenhouse gases mitigation. Oxygen (O2) is one of the significant factors in methane bio-oxidation. The O2 concentration in the environments not only can affect community structure and activity of aerobic methanotrophs and the distribution of methane-derived carbon, but also aerobic methanotrophs have various ways of metabolism at different O2 concentrations. It is meaningful for carbon cycle and biodiversity of methane-driven ecosystem to understand the hypoxia-tolerance mechanisms of aerobic methanotrophs and methane bio-oxidation in O2-limited environments. In this paper, the activity and community structure of aerobic methanotrophs in O2-limited environments were summarized. The hypoxia-tolerance mechanism of aerobic methanotrophs and the relationship between methanotrophs and non-methanotrophs in O2-limited environments were reviewed. Future studies about aerobic methanotrophs were also discussed.


Assuntos
Biodiversidade , Metano , Oxigênio , Hipóxia , Oxirredução , Microbiologia do Solo
14.
Genetics ; 205(2): 749-759, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27932542

RESUMO

The evolutionarily conserved TRPA1 channel can sense various stimuli including temperatures and chemical irritants. Recent results have suggested that specific isoforms of Drosophila TRPA1 (dTRPA1) are UV-sensitive and that their UV sensitivity is due to H2O2 sensitivity. However, whether such UV sensitivity served any physiological purposes in animal behavior was unclear. Here, we demonstrate that H2O2-sensitive dTRPA1 isoforms promote avoidance of UV when adult Drosophila females are selecting sites for egg-laying. First, we show that blind/visionless females are still capable of sensing and avoiding UV during egg-laying when intensity of UV is high yet within the range of natural sunlight. Second, we show that such vision-independent UV avoidance is mediated by a group of bitter-sensing neurons on the proboscis that express H2O2-sensitive dTRPA1 isoforms. We show that these bitter-sensing neurons exhibit dTRPA1-dependent UV sensitivity. Importantly, inhibiting activities of these bitter-sensing neurons, reducing their dTRPA1 expression, or reducing their H2O2-sensitivity all significantly reduced blind females' UV avoidance, whereas selectively restoring a H2O2-sensitive isoform of dTRPA1 in these neurons restored UV avoidance. Lastly, we show that specifically expressing the red-shifted channelrhodopsin CsChrimson in these bitter-sensing neurons promotes egg-laying avoidance of red light, an otherwise neutral cue for egg-laying females. Together, these results demonstrate a physiological role of the UV-sensitive dTRPA1 isoforms, reveal that adult Drosophila possess at least two sensory systems for detecting UV, and uncover an unexpected role of bitter-sensing taste neurons in UV sensing.


Assuntos
Células Quimiorreceptoras/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Oviposição/genética , Canais de Cátion TRPC/genética , Raios Ultravioleta , Animais , Células Quimiorreceptoras/efeitos dos fármacos , Células Quimiorreceptoras/efeitos da radiação , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Feminino , Peróxido de Hidrogênio/farmacologia , Canais Iônicos , Locomoção , Oviposição/efeitos da radiação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Canal de Cátion TRPA1 , Canais de Cátion TRPC/metabolismo , Paladar
15.
Pharmacogenomics ; 17(18): 2007-2014, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27918244

RESUMO

AIM: The clinical efficacy of valproic acid (VPA) varies greatly among epileptic patients. To find the potential genetic factors related to VPA responses, the pharmacogenetics study was conducted. METHODS: Two hundred and one Chinese Han epileptic patients who were treated by VPA for at least 1 year were recruited. Up to 24 SNPs in 11 candidate genes that correlate with the metabolism, transport or target of VPA were genotyped. RESULTS: Three SNPs, rs1731017 (ABAT), rs2304016 (SCN2A) and rs1054899 (ALDH5A1) were found associated with VPA responses with the p-values of 0.003, 0.007 and 0.048, respectively. Further interaction analysis showed that the interaction between rs17183814 (ABAT) and rs1641022 (SCN2A) was also correlated with the response of VPA (p = 0.006). CONCLUSION: This study found three SNPs and one interaction among ABAT, SCN2A and ALDH5A1 were significantly associated with VPA response, which indicated that these genes may play important roles in the pharmacological mechanism of VPA.


Assuntos
4-Aminobutirato Transaminase/genética , Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Canal de Sódio Disparado por Voltagem NAV1.2/genética , Polimorfismo de Nucleotídeo Único , Succinato-Semialdeído Desidrogenase/genética , Ácido Valproico/uso terapêutico , Adolescente , Criança , Pré-Escolar , Epilepsia/genética , Feminino , Humanos , Masculino , Adulto Jovem
16.
Cancer Res ; 76(23): 6924-6936, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27758890

RESUMO

Fatty acid synthase (FASN) is the terminal enzyme in de novo lipogenesis and plays a key role in cell proliferation. Pharmacologic inhibitors of FASN are being evaluated in clinical trials for treatment of cancer, obesity, and other diseases. Here, we report a previously unknown mechanism of FASN regulation involving its acetylation by KAT8 and its deacetylation by HDAC3. FASN acetylation promoted its degradation via the ubiquitin-proteasome pathway. FASN acetylation enhanced its association with the E3 ubiquitin ligase TRIM21. Acetylation destabilized FASN and resulted in decreased de novo lipogenesis and tumor cell growth. FASN acetylation was frequently reduced in human hepatocellular carcinoma samples, which correlated with increased HDAC3 expression and FASN protein levels. Our results suggest opportunities to target FASN acetylation as an anticancer strategy. Cancer Res; 76(23); 6924-36. ©2016 AACR.


Assuntos
Processos de Crescimento Celular/genética , Ácido Graxo Sintases/genética , Lipogênese/genética , Acetilação , Proliferação de Células , Humanos , Transdução de Sinais , Microambiente Tumoral
17.
J Vis Exp ; (109): e53716, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27077482

RESUMO

Recently, egg-laying preference of Drosophila has emerged as a genetically tractable model to study the neural basis of simple decision-making processes. When selecting sites to deposit their eggs, female flies are capable of ranking the relative attractiveness of their options and choosing the "greater of two goods." However, most egg-laying preference assays are not practical if one wants to take a systematic genetic screening approach to search for the circuit basis underlying this simple decision-making process, as they are population-based and laborious to set up. To increase the throughput of studying of egg-laying preferences of single females, we developed custom chambers that each can simultaneously assay egg-laying preferences of up to thirty individual flies as well as a protocol that ensures each female has a high egg-laying rate (so that their preference is readily discernable and more convincing). Our approach is simple to execute and produces very consistent results. Additionally, these chambers can be equipped with different attachments to allow video recording the egg-laying animals and to deliver light for optogenetics studies. This article provides the blueprints for fabricating these chambers and the procedure for preparing the flies to be assayed in these chambers.


Assuntos
Tomada de Decisões/fisiologia , Drosophila melanogaster/fisiologia , Modelos Animais , Oviposição/fisiologia , Animais , Proteínas de Drosophila/genética , Feminino
18.
Environ Sci Pollut Res Int ; 23(8): 7517-28, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26728286

RESUMO

Methanotrophs not only play an important role in mitigating CH4 emissions from the environment, but also provide a large quantity of CH4-derived carbon to their habitats. In this study, the distribution of CH4-derived carbon and microbial community was investigated in a consortium enriched at three O2 tensions, i.e., the initial O2 concentrations of 2.5 % (LO-2), 5 % (LO-1), and 21 % (v/v) (HO). The results showed that compared with the O2-limiting environments (2.5 and 5 %), more CH4-derived carbon was converted into CO2 and biomass under the O2 sufficient condition (21 %). Besides biomass and CO2, a high conversion efficiency of CH4-derived carbon to dissolved organic carbon was detected in the cultures, especially in LO-2. Quantitative PCR and Miseq sequencing both showed that the abundance of methanotroph increased with the increasing O2 concentrations. Type II methanotroph Methylocystis dominated in the enrichment cultures, accounting for 54.8, 48.1, and 36.9 % of the total bacterial 16S rRNA gene sequencing reads in HO, LO-1, and LO-2, respectively. Methylotrophs, mainly including Methylophilus, Methylovorus, Hyphomicrobium, and Methylobacillus, were also abundant in the cultures. Compared with the O2 sufficient condition (21 %), higher microbial biodiversity (i.e., higher Simpson and lower Shannon indexes) was detected in LO-2 enriched at the initial O2 concentration of 2.5 %. These findings indicated that compared with the O2 sufficient condition, more CH4-derived carbon was exuded into the environments and promoted the growth of non-methanotrophic microbes in O2-limiting environments.


Assuntos
Carbono/análise , Metano/análise , Methylocystaceae/crescimento & desenvolvimento , Consórcios Microbianos , Oxigênio/química , Microbiologia do Solo , Biodiversidade , Biomassa , Ecossistema , Metano/química , Methylocystaceae/isolamento & purificação , Methylocystaceae/metabolismo , Oxirredução , RNA Ribossômico 16S/genética
19.
Huan Jing Ke Xue ; 37(8): 2897-2905, 2016 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964713

RESUMO

A total of 396 rainwater samples of Guilin from 2008 to 2011 were collected and analyzed for pH, 44 of which were analyzed for major ions. The analysis of pH values showed the obvious seasonal variation of acid rain in Guilin. The pollution level of summer was lower than those in other seasons, while the pollution levels in winter and spring were the highest. The investigation of fractional acidity(AF) and neutralization factors(NF) indicated that low acid rain pollution level in 2008 was caused by alkali neutralization, especially NH4+ and Ca2+. Studies of the origins of major ions showed that CI- and Na+ were mainly from sea, Ca2+ was mainly from the crustal dust while K+, SO42- and NO3- were mainly originated from anthropogenic source. Finally, the effect of regional transportation on acid rain of Guilin was analyzed and 3 originatons of acid-causing substance were oriented by an air trajectory clustering methodology based on hysplit-4 and a clustering algorithm including 1Jiangxi, Anhui, Hunan and Hubei, with high population densities, these regions contributed 19% air mass in spring, 26% in summer, 19% in autumn and 36% in winter due to the northeast wind; 2Pearl River Delta, with airflow from west Pacific passing before arriving Guilin, contributing 19% in spring, 33% in autumn and 36% in winter; 3Nanning, Liuzhou. All strong acid rain vapor air mass converged in southwest Guilin in spring, and arrived in Guilin passing Naning and Liuzhou. In summer, under the direct control of southwest monsoon, the vapor from Indian Ocean directly arrived in Guilin, accounting for 75%. The southwest airflow passing these cities accounted for 14% in autumn and 63% in winter.

20.
Pharmacogenomics ; 17(1): 74-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26652861

RESUMO

ß-ARs are extensively spread in different tissues of our body, which could be activated by neurotransmitters norepinephrine and epinephrine to mediate physiological function and abnormal states including cancer. Recently, ß-AR blockers could have significant implications in cancer therapy. But the precise molecular mechanisms are far from being fully understood. Through identifying the ß-AR system signal pathways relevant to cancer, we can understand the mechanisms of ß-blockers used for cancer treatment. What's more, retrospective clinical data made ß-blockers jump out of the traditional field of cardiovascular disease and strengthened our confidence in cancer therapy. At last, genetic studies of ß-adrenergic system offered crucial genes to analyze the effects of polymorphisms on cancer susceptibility, therapy response and prognosis of cancer patients.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/genética , Polimorfismo Genético , Receptores Adrenérgicos beta/genética , Quimioterapia Adjuvante , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Receptores Adrenérgicos beta/fisiologia , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA