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1.
Sci Rep ; 10(1): 7891, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398757

RESUMO

Improving soil structure, fertility, and production is of major concern for establishing sustainable agroecosystems. Further research is needed to evaluate whether different methods of straw returning determine the variations of soil aggregation and the microbial community in aggregates in the long term. In this study, we comparatively investigated the effects of long-term fertilization regimes performed over six years, namely, non-fertilization (CK), chemical fertilization (CF), continuous straw return (CS), and continuous straw-derived biochar amendment (CB), on soil aggregation and bacterial communities in rice-wheat rotation systems. The results showed that straw/biochar application increased soil nutrient content and soil aggregate size distribution and stability at both 0-20 cm and 20-40 cm soil depths, compared with those of CF and CK; CB performed better than CS. CB increased bacterial community diversity and richness in 0-20 cm soil, and evenness in 0-40 cm soil (p < 0.05); CS had no significant effect on these aspects. Variations in the relative abundance of Actinobacteria, Chloroflexi, Bacteroidetes, Nitrospirae, Gemmatimonadetes, and Latescibacteria in specific aggregates confirmed the different effects of straw/biochar on bacterial community structure. The partial least squares discrimination analysis and permutation multivariate analysis of variance revealed that fertilization, aggregate size fractions, and soil depth affected the bacterial community, although their effects differed. This study suggests that CB may reduce chemical fertilizer usage and improve the sustainability of rice-wheat cropping systems over the long term, with a better overall outcome than CS.

2.
J Hazard Mater ; 395: 122644, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32315798

RESUMO

Dictyosphaerium sp. is tolerant to nonylphenol (NP); however, knowledge regarding the mechanisms involved in NP tolerance is limited. In this study, a batch of algal culture experiments were carried out to elucidate the underlying mechanisms by investigating the production and composition of extracellular polymeric substances (EPS) in algae exposed to NP. The excretion of EPS was significantly enhanced (P < 0.001) in algae exposed to 4 and 8 mg/L of NP. The polysaccharides in soluble EPS and the proteins in bound EPS were specifically overproduced. The three-dimensional excitation and emission matrix fluorescence spectra analyses indicated that tyrosine- and tryptophan-like substances were the main functional compositions in the proteins of EPS. In addition, enhanced EPS secretion significantly alleviated the toxicity of NP to the algae by the reduction of cell internalization, as indicated by the higher IC50, biomass, and cell growth rate in the algae with EPS. These discoveries along with the characterizations by algal cell surface hydrophobicity analysis, scanning electron microscopy, and Fourier transform infrared spectra spectroscopy demonstrated the vital role of EPS in the algal resistance to NP.

3.
Psychol Health Med ; : 1-12, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32098490

RESUMO

This study aimed to investigate the relationships between cognitive emotion regulation (CER) strategies, resilience, and insomnia and the underlying mechanism that explains the relationships. Six hundred and fifty-three middle-aged and old people recruited from community service centers in Henan province completed questionnaires related to CER strategies, resilience, and insomnia. Results showed refocus on planning and positive reappraisal negatively predicted insomnia, and catastrophising, rumination and self-blame positively predicted insomnia. Moreover, maladaptive emotion regulation strategies (especially catastrophising) mediated the relationship between resilience and insomnia. The findings suggest the middle-aged and elderly with insomnia tended to employ maladaptive emotion regulation strategies and had lower resilience. Maladaptive emotion regulation strategies buffered the positive effect of resilience on sleep.

4.
Stroke ; 51(1): 149-153, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31679502

RESUMO

Background and Purpose- Studies on the prevalence and risk factors of white matter lesions (WMLs) in Tibetans living at high altitudes are scarce. We conducted this study to determine the prevalence and risks of WMLs in Tibetan patients without or with nonacute stroke. Methods- We undertook a retrospective analysis of medical records of patients treated at the People's Hospital of Tibetan Autonomous Region and identified a total of 301 Tibetan patients without acute stroke. WML severity was graded by the Fazekas Scale. We assessed the overall and age-specific prevalence of WMLs and analyzed associations between WMLs and related factors with univariate and multivariate methods. Results- Of the 301 patients, 87 (28.9%) had peripheral vertigo, 83 (27.3%) had primary headache, 52 (17.3%) had a history of stroke, 36 (12.0%) had an anxiety disorder, 29 (9.6%) had epilepsy, 12 (4.0%) had infections of the central nervous system, and 3 (1.0%) had undetermined diseases. WMLs were present in 245 (81.4%) patients, and 54 (17.9%) were younger than 40 years. Univariate analysis showed that age, history of cerebral infarction, hypertension, the thickness of the common carotid artery intima, and plaque within the intracarotid artery were related risks for WMLs. Ordered logistic analysis showed that age, history of cerebral ischemic stroke, hypertension, male sex, and atrial fibrillation were associated with WML severity. Conclusions- Risk factors for WMLs appear similar for Tibetans residing at high altitudes and individuals living in the plains. Further investigations are needed to determine whether Tibetans residing at high altitudes have a higher burden of WMLs than inhabitants of the plains.


Assuntos
Infecções do Sistema Nervoso Central , Cefaleia , Vertigem , Substância Branca/fisiologia , Doença Aguda , Adulto , Fatores Etários , Idoso , Infecções do Sistema Nervoso Central/epidemiologia , Infecções do Sistema Nervoso Central/patologia , Feminino , Cefaleia/epidemiologia , Cefaleia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/patologia , Tibet/epidemiologia , Vertigem/epidemiologia , Vertigem/patologia
5.
J Biochem Mol Toxicol ; 34(2): e22429, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31860774

RESUMO

Alzheimer's disease (AD) is an age-associated neurodegenerative disease, which is developed by oxidative stress and acetylcholine contraction in the synaptic cleft of the neurons. This leads to dementia, memory loss, and decrease in learning ability and orientation. In this research work, we aimed to explore the neuroprotective effect of neferine on AlCl3 -induced AD in rats. The results of our study revealed that the increased reactive oxygen species (ROS) and nitric oxide in the hippocampus leads to the development of AD in the rats. The oral treatment of neferine done the following occurrences such as; it potentially inhibited the ROS formation and acts as a scavenging molecule by preventing the neurodegeneration. It also improved the memory and learning ability to complete the maze activity in the AD rats and significantly increased the antioxidants superoxide dismutase, catalase, and reduced glutathione in neferine treated AD rats. It aggressively declined the activity of acetylcholine esterase and Na+ K+ ATPase in the neurodegenerative rat models. The gene expression pattern of neuroinflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) were decreased in the neferine-treated rats. The neuroinflammatory proteins such as inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa ß (Nf-κß) were decreased and Nf-κß inhibitor IKBα was increased in the neferine-treated AD rats. Finally, the histology study proved that the neferine treatment possibly prevents neurodegeneration in the hippocampus tissue of the AD models. Hence, these all findings concluded that the neferine could be a potential neuropreventive as well as neurodegenerative therapeutic compound in neurological and cognitive dysfunction.


Assuntos
Cloreto de Alumínio/farmacologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Benzilisoquinolinas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Administração Oral , Cloreto de Alumínio/efeitos adversos , Animais , Comportamento Animal/efeitos dos fármacos , Benzilisoquinolinas/administração & dosagem , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Expressão Gênica/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , NF-kappa B/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Óxido Nítrico Sintase Tipo II/metabolismo , Nootrópicos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
6.
Sci Total Environ ; 705: 136003, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31846813

RESUMO

Chitin amendment is a promising agricultural management strategy to control fungal and nematodal plant diseases and to improve crop yield. Chitin degradation in the soil contributes significantly to carbon and nitrogen cycling in terrestrial ecosystems. However, little is known about chitin degradation and bacterial chitinolytic communities in agricultural soil under different fertilization regimes. Thus, in the present study, a 42-day soil incubation experiment was conducted, in which soil under four fertilization regimes (i.e., no fertilization (CK), chemical fertilizer (CF), pig manure plus 50% chemical fertilizer (PMCF), and rice straw plus 100% chemical fertilizer (SRCF)) were amended or not with chitin or its monomer, N-acetylglucosamine (NAG). Different nitrogen forms and CO2 and N2O emission were measured to evaluate chitin degradation and its environmental implications. SRCF soil had the highest CO2 emission, chitin N mineralization, and fungal abundance. NAG and chitin were enriched to exploit the chitin degraders. High-throughput sequencing analyses reveled that Streptomycetaceae, Oxalobacteraceae, Gemmatimonadaceae, and Acidobacteria were generally increased upon chitin amendment in CK, CF, and PMCF soil, whereas Streptomycetaceae dominated chitin-amended SRCF soil. Herpetosiphonaceae was enriched only in chitin-amended CK soil. LEfSe and network analysis were used to predict chitinolytic and opportunistic species, and revealed that most previously reported chitinolytic bacteria were detected in the present study and new potential chitin degraders, including unidentified_Solibacterales, Gemmatimonadaceae, and Herpetosiphonaceae, were identified. Some members of Firmicutes, Actinobacteria, and Proteobacteria, including Bacillus, and Kitasatospora, were speculated to be opportunistic species. The findings improve our understanding of the effects of chitin degradation on carbon and nitrogen cycling in agricultural soil under different fertilization regimes and help to identify chitinolytic bacteria.


Assuntos
Solo , Animais , Bactérias , Quitina , Ecossistema , Fertilizantes , Microbiologia do Solo , Suínos
7.
Medicine (Baltimore) ; 98(44): e17845, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689875

RESUMO

BACKGROUND: Shegan Mahuang Decoction (SMD) was used widely for treatment of asthma in China; however, the clinical effect of SMD on asthma was not well concluded. METHODS: Seven electronic databases (Medline, Cochrane library, EMBASE database, Chinese National Knowledge Infrastructure, Wanfang database, Chongqing VIP database, and Chinese Biomedicine database) will be searched for randomized controlled trials which meet the eligible criteria. Two reviewers will select studies and extract data independently. Risk of bias will be evaluated using modified Jadad score. Data synthesis will be carried out using RevMan 5.3. Sensitivity analysis and publication bias will also be investigated. RESULTS: This systematic review and meta-analysis will review and synthesis current clinical evidence of SMD for the treatment of asthma. CONCLUSION: This systematic review and meta-analysis will provide high quality evidence of SMD for the treatment of asthma. REGISTRATION: PROSPERO CRD42019141810.


Assuntos
Asma/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Metanálise como Assunto , Preparações de Plantas/uso terapêutico , Revisões Sistemáticas como Assunto , Adolescente , Adulto , Idoso , Humanos
8.
Food Funct ; 10(10): 6675-6689, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31559407

RESUMO

Dietary betaine supplementation notably ameliorated fatty liver disease caused by high dietary carbohydrate. We hypothesised that the mechanism behind this is the alteration of bile acid and trimethylamine-N-oxide (TMAO) metabolism. We further explored this mechanism by supplementing betaine (1%) to the diet of a farmed fish Megalobrama amblycephala. Four diet groups were designed: control (CD, 27.11% carbohydrates), high-carbohydrate (HCD, 36.75% carbohydrates), long-term betaine (HCB, 35.64% carbohydrates; 16 weeks) and short-term betaine (HC4B; 12 weeks HCD + 4 weeks HCB) diets. We analysed the histology of the liver (hematoxylin and eosin staining), the metabolites related to TMAO in plasma (high-performance liquid chromatography-tandem mass spectrometry), the expression of the relative gene in the liver and gut microbiota (qPCR), and the composition of gut microbiota (terminal restriction fragment length polymorphism). HCD elevated lipid accumulation in the liver and decreased the gene expression of bile acid transport, trimethylamine (TMA) formation and the diversity of gut microbiota compared to CD. HCB reversed these patterns, and elevated the gene expression of bile acid receptors and decreased the total cholesterol and TMAO concentration (all compared to HCD). HCD and HCB both increased the gene expression of bile acid synthesis (all p < 0.05). In conclusion, we hypothesise that HCB decreased liver lipid accumulation caused by a high-carbohydrate diet through improvement of the gut microbial community (the diversity of gut microbiota), TMA formation (the expression of associated microbial genes and bacterial taxa), TMAO metabolism (the formation of TMAO) and bile acid metabolism (the gene expression of the synthesis and transport of bile acids and their receptors). HC4B produced intermediate effects of those between HCD and HCB.


Assuntos
Betaína/metabolismo , Ácidos e Sais Biliares/metabolismo , Cyprinidae/metabolismo , Fígado/metabolismo , Metilaminas/metabolismo , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/microbiologia , Microbioma Gastrointestinal
9.
Sci Total Environ ; 694: 133658, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398644

RESUMO

Biochar has been demonstrated to reduce nitrous oxide (N2O) emissions from soils, but its effect is highly soil-dependent. In particular, in soils with strong nitrification potential, biochar addition may increase N2O emissions. Thus, in soils with strong nitrification potential, the combination of biochar with the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) may be more effective in reducing N2O emissions than biochar alone. However, the combined use of biochar and DMPP on soil N2O emissions is relatively unexplored, and underlying microbial mechanisms of how biochar and/or DMPP amendment affect N2O emissions is still largely unknown. Here, a 30-day incubation experiment was established with four treatments: CK (control), BC (biochar), DMPP, and BD (biochar and DMPP), all at agronomically recommended rates, and N cycling assessed following addition of urea. Treatment of soil with BC, DMPP and BD reduced N2O emissions (compared with urea alone) by 59.1%, 95.5% and 74.1%, respectively. Quantification of N cycling genes (amoA, nirS, nirK, and nosZ) indicated that biochar stimulated growth of ammonia oxidizing archaea (AOA) and bacteria (AOB), while DMPP alone inhibited the activity and growth of AOB. In the BD treatment, DMPP was absorbed onto biochar reducing its efficacy in inhibiting AOB growth. The response patterns of nirS/nirK nitrite-reducing denitrifiers to biochar and/or DMPP addition varied among clades. Notably, biochar and/or DMPP increased the abundance of nosZI and nosZII-N2O reducers, but nosZI-clade taxa were more closely associated with reducing N2O emission than nosZII taxa. Overall, our findings proved that the dynamics of AOB and nosZI-N2O reducers resulting from the addition of biochar and/or DMPP played a key role in governing soil N2O emissions.


Assuntos
Amônia/química , Carvão Vegetal/química , Dióxido de Nitrogênio/análise , Pirazóis/química , Microbiologia do Solo , Biodegradação Ambiental , Solo/química
10.
Environ Int ; 130: 104913, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31254866

RESUMO

Anammox bacteria are the key microbes after denitrifiers in the anaerobic environment. Nitrogen gap cannot be satisfied till date even with the advanced techniques, due to complex microbial network and different pathways. Recently, anaerobic fungi are the concerning point to investigate, which was previously ignored for a long time. Study was conducted with the aim of assessment of an individual and combined contribution of anammox, co-denitrification, and denitrification processes for N losses, under different organic-chemical fertilizers, i.e. 1) control _CK; 2) chemical fertilization _CF; 3) pig manure plus chemical fertilization _PMCF; and 4) straw returned plus chemical fertilization _SRCF). Hybrid techniques of 13C-DNA-Stable isotope and 15N isotopic tracer were used to discriminate the contribution of anammox-co-fungi using antibacterial and antifungal inhibitors. Results showed that fungi are the major culprit in N losses; the overall contribution rate by anammox-co-denitrification was 14.82-29.74%. While in case of individual N losses, fungi were dominating the N losses (3.51-25.60%, AB) than bacteria (7.50-21.80%, AF). The anammox and fungi have a positive correlation with each other's (r = 0.67), principal component analysis (PCA) and correlation analysis validate each other (anammox and fungi), and both showed the same type of attraction to the soil physicochemical properties. However, fungi did not show a significant relationship with NH+4-N (r = 0.38). A clone library of 13C-DNA-SIP was constructed, and results showed that denitrifying fungi were very likely belonges to the genera Agaricus, Aspergillus, Phycomyces, Saitoella, and Trichoderma. Conclusively, we propose that fertilization pattern can change anammox activity and abundance, but fungal activity and community structure undergo changes with organic amendments rather than inorganic fertilizers.


Assuntos
Compostos de Amônio/metabolismo , Bactérias Anaeróbias/metabolismo , Fungos/metabolismo , Ciclo do Nitrogênio , Microbiologia do Solo , China , Produção Agrícola , Oryza/crescimento & desenvolvimento , Oxirredução , Triticum/crescimento & desenvolvimento
11.
Sci Total Environ ; 687: 416-422, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31212149

RESUMO

Algal cultures of Dictyosphaerium sp. were treated with a wide range (0-8 mg/L) of nonylphenol (NP) applications to investigate the species' potential to perform bioremediation of NP-contaminated wastewater and explore the mechanism of NP toxicity in algal cell. The algal species exhibited a high tolerance for NP and efficiently removed even high concentrations of NP. The accumulation of NP in algal cells tended to increase and the percentage of NP adhered to the cell walls tended to decrease as the NP concentration increased. The thylakoid density and the pyrenoid size also tended to decrease as the NP concentration rose. The key genes involved in the antioxidative pathways and photosynthetic pathways were down-regulated in the NP-treated algal cells. Algal ribosome genes were especially sensitive to NP. The results indicated that NP could induce oxidative stress in algal cells and that Dictyosphaerium sp. showed potential as a bioremediation agent.


Assuntos
Clorófitas/fisiologia , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Biodegradação Ambiental , Fotossíntese , Transcriptoma
12.
J Alzheimers Dis ; 70(1): 121-129, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31127789

RESUMO

Recent studies suggest that severity of asthma can be modulated by neuropsychiatric conditions, while the underlying mechanisms are not clear. Here, we used ovalbumin (OVA) to induce asthma in APP/PS1 mice, a mouse model of Alzheimer's disease (AD), or in their wildtype control C57BL/6J mice. We found that all hallmarks of asthma by OVA were significantly attenuated in APP/PS1 mice, compared to age- and gender-matched C57BL/6J mice. Interestingly, significantly higher number of regulatory T cells (Treg) was detected in the APP/PS1 mouse lung, compared to those in the C57BL/6J mouse lung. Since Foxp3 is crucial for differentiation of naive T cells into Treg and is the most important marker for Treg, we examined the Foxp3 levels in the T cells from the lung of these mice. We found that the Foxp3 levels in the APP/PS1 mouse lung were significantly higher than those in the C57BL/6J mouse lung, likely resulting from reduced Foxp3 promoter methylation. Thus, our study suggests that AD may affect severity of asthma through methylation control of Foxp3 promoter in T cells.

13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(1): 55-60, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31037905

RESUMO

OBJECTIVE: To investigate the effect of small interfering RNA of lactate dehydrogenase A (siLDHA) on migration and invasion of epidermal growth factor receptor 2 (ErbB2) over expressing breast cancer cell line SK-BR-3, MDA-MB-453 and its molecular mechanism. METHODS: SK-BR-3 and MDA-MB-453 cells were transfected with siLDHA to interfere with the expression of LDHA. The transfection of scramble siRNA was used as negative control. The LDHA protein levels were detected by Western blot ( P<0.01). Cell migration and invasion was detected by Transwell assays. Lactate dehydrogenase (LDH) activity was measured by LDH assay kit. The glucose and lactate concentration in the culture media was determined by glucose and lactate assay kit, respectively, and then glucose uptake and lactate production by the cells were calculated. RESULTS: siLDHA downregulated LDHA protein levels in SK-BR-3 and MDA-MB-453 cells ( P<0.01). Compared with negative control group, siLDHA significantly decreased migration and invasion of SK-BR-3 and MDA-MB-453 cells ( P<0.001). siLDHA reduced LDH activity in SK-BR-3 cells, glucose uptake and lactate production in SK-BR-3 and MDA-MB-453 cells, the difference was significant ( P<0.05). CONCLUSION: Knockdown of LDHA by siRNA inhibits the migration and invasion via downregulation of glycolysis in ErbB2 over expressing breast cancer cell line.


Assuntos
Neoplasias da Mama , L-Lactato Desidrogenase/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Células MCF-7 , RNA Interferente Pequeno , Receptor ErbB-2
14.
Environ Pollut ; 249: 686-695, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30933766

RESUMO

Although fertilization plays an important role in determining the contents of soil dissolved organic matters or water-extractable organic matter (DOM, WEOM), knowledge regarding the dynamics, biodegradability, and microbial community shifts of WEOM in response to different fertilization treatments is very limited, particularly in rice-wheat cropping soil. Thus, in the present study, we performed biodegradation experiments using WEOM extracted from samples of soil that had been subjected to four different fertilization treatments: unfertilized control (CK), chemical fertilizer (CF), 50% chemical fertilizer plus pig manure (PMCF), and 100% chemical fertilizer plus rice straw (SRCF). UV spectrum and fluorescence 3D excitation-emission matrix analyses applied to investigate the chemical composition of WEOM revealed that all examined WEOMs were derived from microbial activity and the dominant portion comprised humic acid-like compounds. After the incubation, 31.17, 31.63, 43.47, and 33.01% of soil WEOM from CK, CF, PMCF, and SRCF treatments, respectively, were biodegraded. PMCF- derived WEOM had the highest biodegradation rate. High-throughput sequencing analyses performed to determine the microbial community before and after the incubation indicated that Sphingomonas, Bacillus, and Flavisolibacter were the predominant bacterial genera in the original inoculum derived from the four fertilization treatments. Following biodegradation, we observed that the dominant bacteria differed according to fertilization treatments: Curvibacter (43.25%) and Sphingobium (10.47%) for CK, Curvibacter (29.68%) and Caulobacter (20.00%) for CF, Azospirillum (23.68%) and Caulobacter (13.29%) for PMCF, and Ralstonia (51.75%) for SRCF. Canonical correspondence analysis revealed that, shifts in the microbial community were closely correlated with pH and specific UV absorbance at 254 nm. We speculated that the inherent traits of different WEOM and the properties of soil solutions under different fertilization treatments shaped the soil microbial community structure, thereby influencing the biodegradation of WEOM.


Assuntos
Fertilizantes/análise , Substâncias Húmicas/análise , Oryza/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Triticum/crescimento & desenvolvimento , Animais , Biodegradação Ambiental , Esterco/análise , Microbiota , Oryza/química , Sphingomonas/isolamento & purificação , Suínos , Água/química
15.
Sci Total Environ ; 672: 305-313, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959297

RESUMO

Anammox are unusual members of the microbial community contributing to N losses via anaerobic ammonium oxidation. Anammox use nitrite as a substrate and produce hydrazine as an intermediate product. Up to date, the effects of dissolved oxygen and moisture dynamics on anammox potential and microbial community in agricultural soils were poorly understood. In this study, we investigated the interaction of dissolved oxygen and moisture contents as factors affecting the soil anammox process. The experiment had four fertilization treatments i.e. Control (CK), Chemical fertilizer (CF), Pig composted manure plus chemical fertilizer (PMCF), and Straw returned to soil plus chemical fertilizer (SRCF) with different water contents, 70%-FC, Alternate wetting and drying (AWD), Flooding I (D.O 5.8 mg L-1), and Flooding II (D.O 2.6 mg L-1). 15N-isotopic tracer technique was used to evaluate the anammox and denitrification rates. The results showed that the anammox rate ranged from the lowest 0.56 nmol N2·g-1·h-1 in CF (with 70% FC water) to the highest rate of 1.47 nmol N2·g-1·h-1 in SRCF (with flooding II). In water treatments, the average lowest and highest anammox rates were in the 70% FC (0.61 nmol N2·g-1·h-1) and Flooding II (1.14 nmol N2·g-1·h-1), respectively. Moreover, under soil treatments, the minimum average anammox rate was found in the PMCF (0.76 nmol N2·g-1·h-1) and maximum in the SRCF (1.01 nmol N2·g-1·h-1). Interestingly, anammox genes copy numbers were highest in alternate wetting and drying conditions under all fertilizer treatments rather than in continuous flooding. The phylogenetic analysis showed that Ca. Brocadia was dominating while some of Ca. Jettenia was also present. In conclusion, alternate wetting and drying could increase the number of anammox bacteria and microbial diversity.


Assuntos
Agricultura/métodos , Oxigênio/análise , Microbiologia do Solo , Compostos de Amônio/análise , Compostos de Amônio/metabolismo , Anaerobiose , Animais , Bactérias , China , Desnitrificação , Fertilizantes/análise , Inundações , Esterco/análise , Microbiota , Nitritos/análise , Oryza/crescimento & desenvolvimento , Oxirredução , Filogenia , Poaceae , Solo/química , Suínos , Triticum/crescimento & desenvolvimento
16.
Genome ; 62(2): 53-67, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30830800

RESUMO

Expensive and unsustainable fishmeal is increasingly being replaced with cheaper lipids and carbohydrates as sources of energy in aquaculture. Although it is known that the excess of lipids and carbohydrates has negative effects on nutrient utilization, growth, metabolic homeostasis, and health of fish, our current understanding of mechanisms behind these effects is limited. To improve the understanding of diet-induced metabolic disorders (both in fish and other vertebrates), we conducted an eight-week high-fat-high-carbohydrate diet feeding trial on blunt snout bream (Megalobrama amblycephala), and studied gene expression changes (transcriptome and qPCR) in the liver. Disproportionately large numbers of differentially expressed genes were associated with mitochondrial metabolism, neurodegenerative diseases (Alzheimer's, Huntington's, and Parkinson's), and functional categories indicative of liver dysfunction. A high-fat-high-carbohydrate diet may have caused mitochondrial dysfunction, and possibly downregulated the mitochondrial biogenesis in the liver. While the relationship between diet and neurodegenerative disorders is well-established in mammals, this is the first report of this connection in fish. We propose that fishes should be further explored as a potentially promising model to study the mechanisms of diet-associated neurodegenerative disorders in humans.


Assuntos
Cyprinidae/genética , Dieta Hiperlipídica/efeitos adversos , Doenças dos Peixes/etiologia , Mitocôndrias Hepáticas/metabolismo , Transcriptoma , Ração Animal/efeitos adversos , Animais , Cyprinidae/metabolismo , Mitocôndrias Hepáticas/genética , Mitocôndrias Hepáticas/patologia
17.
Appl Microbiol Biotechnol ; 103(7): 3099-3109, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30788541

RESUMO

Cupriavidus basilensis WS degrades diphenyl ether (DE) and its lower brominated derivatives using enzymes encoded by the bph operon. However, it is not yet known under what circumstances bph genes are expressed and how they are regulated in C. basilensis WS. To answer these questions, we used transposon mutagenesis and identified a new two-component regulatory system, BphS/BphT, in C. basilensis WS, which is indispensable for the expression of the bph operon. When BphS or BphT is inactivated, C. basilensis WS no longer exhibits the ability to decompose DE. Using a ß-galactosidase reporter system and RT-qPCR, we showed that bph genes are constitutively transcribed in C. basilensis WS and that deletion of bphS or bphT strongly inhibited the transcription of bph genes. We also showed that the gene ORF0, which is upstream of bphA1 and is similar to the GntR-family regulators of the bph operon, is not involved in the constitutive transcription of the bph operon in C. basilensis WS. The cis-acting elements required for the expression and regulation of bph genes in the DE degradation pathway are included in the intergenic region between ORF0 and bphA1. Our results suggest that BphS/BphT represents a new two-component regulatory system for the bph operon that is necessary for the constitutive expression of bph genes.


Assuntos
Proteínas de Bactérias/genética , Cupriavidus/genética , Regulação Bacteriana da Expressão Gênica , Mutagênese , Óperon , Elementos de DNA Transponíveis , DNA Intergênico , Éteres Fenílicos/metabolismo , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Sequências Reguladoras de Ácido Nucleico , Transcrição Genética , beta-Galactosidase/genética
18.
Mol Cell Biochem ; 453(1-2): 179-186, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30350306

RESUMO

Mycoplasma pneumoniae pneumonia (MPP) is the most common respiratory infection in young children and its incidence has increased worldwide. In this study, high expression of chemokine ligand 5 (CCL5) was observed in the serum of MPP patients, and its expression was positively correlated to DNA of M. pneumoniae (MP-DNA). In vitro, M. pneumoniae (MP) infection to A549 cells induced the expression of CCL5, chemokines receptor 4 (CCR4), nuclear factor-κB (NF-κB) nuclear protein, and phosphorylation of NF-κB-p65 (p-NF-κB-p65), whereas NF-κB cytoplasmic protein was decreased. On the contrary, treatment of hyperoside counteracted the induction of MP infection and promoted the proliferation of MP-infected A549 cells. Similarly, MP-induced IL-8 and TNF-α production was also markedly reduced by hyperoside. And CCR4 inhibitor AZD2098 had a better effect than hyperoside. In addition, CCL5 recombinant protein inhibited the effect of hyperoside to promote IL-8 and TNF-α production and CCR4 expression. These results indicated that CCL5 may be involved in the progression of MPP, and hyperoside was beneficial for MPP probably through CCL5-CCR4 interactions, which may provide a potential effective therapy for MPP.


Assuntos
Células Epiteliais , Mycoplasma pneumoniae/metabolismo , Pneumonia por Mycoplasma , Quercetina/análogos & derivados , Mucosa Respiratória , Células A549 , Quimiocina CCL5/metabolismo , Quimiocina CCL8/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Humanos , Pneumonia por Mycoplasma/tratamento farmacológico , Pneumonia por Mycoplasma/metabolismo , Pneumonia por Mycoplasma/patologia , Quercetina/farmacologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/microbiologia , Mucosa Respiratória/patologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
Sci Rep ; 8(1): 17695, 2018 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-30523308

RESUMO

Prediction of promoter regions is crucial for studying gene function and regulation. The well-accepted position weight matrix method for this purpose relies on predefined motifs, which would hinder application across different species. Here, we introduce image-based promoter prediction (IBPP) as a method that creates an "image" from training promoter sequences using an evolutionary approach and predicts promoters by matching with the "image". We used Escherichia coli σ70 promoter sequences to test the performance of IBPP and the combination of IBPP and a support vector machine algorithm (IBPP-SVM). The "images" generated with IBPP could effectively distinguish promoter from non-promoter sequences. Compared with IBPP, IBPP-SVM showed a substantial improvement in sensitivity. Furthermore, both methods showed good performance for sequences of up to 2,000 nt in length. The performances of IBPP and IBPP-SVM were largely affected by the threshold and dimension of vectors, respectively. The source code and documentation are freely available at https://github.com/hahatcdg/IBPP .


Assuntos
Biologia Computacional/métodos , Escherichia coli/genética , Regiões Promotoras Genéticas/genética , Algoritmos , Máquina de Vetores de Suporte
20.
Int J Biol Macromol ; 119: 1195-1203, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30110602

RESUMO

Schwann cell (SC) is the primary structural and functional part of the peripheral nervous system, and it plays a key role in the repair and regeneration of peripheral nerve. In order to develop a suitable scaffold for SC nerve tissue engineering, three kinds of scaffolds, including pristine collagen, pure oxidized regenerated cellulose-Ca (ORCCa) and collagen/ORC-Ca composite scaffolds, have been fabricated for carrying SC in this study. SC is then seeded on the scaffolds to form SC-scaffold nerve tissue engineering composites and evaluate their biocompatibility. The chemical and physical structure of the scaffolds are investigated by FTIR, NMR and SEM. The wettability of the collagen/ORC-Ca composite scaffold is close to that of pristine collagen, and the tensile strength of the composite scaffold (0.58 MPa) is better than that of pristine collagen (0.36 MPa). Cytotoxicity, cell proliferation, cell adhesion and western blotting assays are conducted to evaluate the biocompatibility and properties of different scaffolds. The results show that the three scaffolds exhibit no toxicity, and the proliferation rate of SC on the collagen/ORC-Ca composite scaffold is significantly higher than that of the other scaffolds (p < 0.05). The number of the adhesion cells on the composite scaffold (244.67 ±â€¯13.02) is much more than that in the pure ORC-Ca group (p < 0.01). Furthermore, the expression of N-Cadheri and PMP22 proteins in the collagen/ORC-Ca composite scaffold is significantly superior to the other two scaffolds (both p < 0.01). Therefore, it could be concluded that the collagen/ORC-Ca composite is a promising candidate as a scaffold for carrying SC to form nerve tissue engineering composites in order to assist the peripheral nervous in the repair and regeneration.


Assuntos
Materiais Biocompatíveis/química , Cálcio/química , Celulose Oxidada/química , Colágeno/química , Portadores de Fármacos/química , Células de Schwann/citologia , Materiais Biocompatíveis/farmacologia , Caderinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Celulose Oxidada/farmacologia , Portadores de Fármacos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Fenômenos Mecânicos , Proteínas da Mielina/metabolismo , Nervos Periféricos/efeitos dos fármacos , Nervos Periféricos/fisiologia , Regeneração , Células de Schwann/química , Molhabilidade
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