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1.
Virol Sin ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39098716

RESUMO

Acinetobacter baumannii (A. baumannii) poses a serious public health challenge due to its notorious antimicrobial resistance, particularly carbapenem-resistant A. baumannii (CRAB). In this study, we isolated a virulent phage, named P1068, from medical wastewater capable of lysing CRAB, primarily targeting the K3 capsule type. Basic characterization showed that P1068 infected the A. baumannii ZWAb014 with an optimal MOI of 1, experienced a latent period of 10 â€‹min and maintained stability over a temperature range of 4-37 â€‹°C and pH range of 3-10. Phylogenetic and average nucleotide identity analyses indicate that P1068 can be classified as a novel species within the genus Obolenskvirus of the Caudoviricetes class as per the most recent virus classification released by the International Committee on Taxonomy of Viruses (ICTV). Additionally, according to classical morphological classification, P1068 is identified as a T4-like phage (Myoviridae). Interestingly, we found that the tail fiber protein (TFP) of P1068 shares 74% coverage and 88.99% identity with the TFP of a T7-like phage (Podoviridae), AbKT21phiIII (NC_048142.1). This finding suggests that the TFP gene of phages may undergo horizontal transfer across different genera and morphologies. In vitro antimicrobial assays showed that P1068 exhibited antimicrobial activity against A. baumannii in both biofilm and planktonic states. In mouse models of intraperitoneal infection, P1068 phage protected mice from A. baumannii infection and significantly reduced bacterial loads in various tissues such as the brain, blood, lung, spleen, and liver compared to controls. In conclusion, this study demonstrates that phage P1068 might be a potential candidate for the treatment of carbapenem-resistant and biofilm-forming A. baumannii infections, and expands the understanding of horizontal transfer of phage TFP genes.

2.
J Affect Disord ; 363: 269-281, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39053628

RESUMO

OBJECTIVE: Schizophrenia (SCZ) and psychotic bipolar disorder (PBD) are two major psychotic disorders with similar symptoms and tight associations on the psychopathological level, posing a clinical challenge for their differentiation. This study aimed to investigate and compare the structural connectivity patterns of the limbic system between SCZ and PBD, and to identify specific regional disruptions associated with psychiatric symptoms. METHODS: Using sMRI data from 146 SCZ, 160 PBD, and 145 healthy control (HC) participants, we employed a data-driven approach to segment the hippocampus, thalamus, hypothalamus, amygdala, and cingulate cortex into subregions. We then investigated the structural connectivity patterns between these subregions at the global and nodal levels. Additionally, we assessed psychotic symptoms by utilizing the subscales of the Brief Psychiatric Rating Scale (BPRS) to examine correlations between symptom severity and network metrics between groups. RESULTS: Patients with SCZ and PBD had decreased global efficiency (Eglob) (SCZ: adjusted P<0.001; PBD: adjusted P = 0.003), local efficiency (Eloc) (SCZ and PBD: adjusted P<0.001), and clustering coefficient (Cp) (SCZ and PBD: adjusted P<0.001), and increased path length (Lp) (SCZ: adjusted P<0.001; PBD: adjusted P = 0.004) compared to HC. Patients with SCZ showed more pronounced decreases in Eglob (adjusted P<0.001), Eloc (adjusted P<0.001), and Cp (adjusted P = 0.029), and increased Lp (adjusted P = 0.024) compared to patients with PBD. The most notable structural disruptions were observed in the hippocampus and thalamus, which correlated with different psychotic symptoms, respectively. CONCLUSION: This study provides evidence of distinct structural connectivity disruptions in the limbic system of patients with SCZ and PBD. These findings might contribute to our understanding of the neuropathological basis for distinguishing SCZ and PBD.


Assuntos
Transtorno Bipolar , Giro do Cíngulo , Hipocampo , Imageamento por Ressonância Magnética , Esquizofrenia , Tálamo , Humanos , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Giro do Cíngulo/diagnóstico por imagem , Masculino , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/fisiopatologia , Esquizofrenia/patologia , Feminino , Adulto , Tálamo/diagnóstico por imagem , Tálamo/patologia , Pessoa de Meia-Idade , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/patologia , Transtornos Psicóticos/fisiopatologia , Estudos de Casos e Controles
3.
J Hazard Mater ; 477: 135309, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39053057

RESUMO

Nanoplastics (NPs) have been demonstrated the ability to penetrate plant roots and cause stress. However, the extent of NPs penetration into various root tissues and the corresponding plant defense mechanisms remain unclear. This study examined the penetration and accumulation patterns of polystyrene nanoplastics (PS-NPs) in different cell types within rice roots, and explored how the roots quickly modify their cell wall structure in response. The findings showed that fully developed sclerenchyma cells in rice roots effectively prevented the invasion of PS-NPs. Meanwhile, PS-NPs triggered the accumulation of lignin and suberin in specific cells such as the exodermis, sclerenchyma, and xylem vessels. PS-NPs at a concentration of 50 mg L-1 increased cell wall thickness by 18.6 %, 21.1 %, and 22.4 % in epidermis, exodermis, and sclerenchyma cells, respectively, and decreased root hydraulic conductivity by 14.8 %. qPCR analysis revealed that PS-NPs influenced the cell wall synthesis pathway, promoting the deposition of lignin and suberin monomers on the secondary wall through the up-regulation of genes such as OsLAC and OsABCG. These results demonstrate that PS-NPs can induce cell type-specific strengthening of secondary walls and barrier formation in rice roots, suggesting the potential role of plant secondary wall development in mitigating NPs contamination risks in crops.


Assuntos
Parede Celular , Lignina , Oryza , Raízes de Plantas , Poliestirenos , Oryza/efeitos dos fármacos , Oryza/metabolismo , Raízes de Plantas/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Poliestirenos/toxicidade , Poliestirenos/química , Lipídeos/química , Nanopartículas/toxicidade , Nanopartículas/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38692473

RESUMO

BACKGROUND: The basal ganglia are important structures for the release of dopamine in the limbic circuits of the midbrain, and the striatum and globus pallidus are the major nuclei of the basal ganglia, and the dysfunction of these regions has been the basis of many models that have attempted to explain the underlying mechanisms of schizophrenia symptoms. The purpose of this study was to investigate the changes in the volume of the striatum subregion and globus pallidus in three different stages of schizophrenia, and to analyze whether these volume changes were related to antipsychotic drugs and schizophrenia symptoms. METHODS: In this study, we investigated the volume of the striatum and globus pallidus in patients with schizophrenia at three different stages. The study included 57 patients with first-episode schizophrenia (FSZ), 51 patients with early-stage schizophrenia (ESZ), 86 patients with chronic schizophrenia (CSZ), and 191 healthy controls (HC), all of whom underwent structured magnetic resonance imaging (MRI) scans. Covariance analysis was performed using SPSS 26.0 was used for covariance analysis to determine whether there were significant differences in striatal subregion and globus pallidus volume between groups, and stratified analysis was used to further eliminate the effect of age on brain volume. Finally, the correlation analysis between the region of interest and the cumulative dose of antipsychotic drugs and psychotic symptoms was performed. RESULTS: The comparison between the different stages of the illness showed significant volume differences in the left caudate nucleus (lCAU) (F = 2.665, adjusted p = 0.048), left putamen (lPUT) (F = 12.749, adjusted p < 0.001), left pallidum (lPAL) (F = 41.111, adjusted p < 0.001), and right pallidum (rPAL) (F = 14.479, adjusted p < 0.001). Post-hoc analysis with corrections showed that the volume differences in the lCAU subregion disappeared. Further stratified analysis controlling for age showed that compared with the HC, the lPAL (t = 4.347, p < 0.001) was initially significantly enlarged in the FSZ group, the lPUT (t = 4.493, p < 0.001), rPUT (t = 2.190, p = 0.031), lPAL (t = 7.894, p < 0.001), and rPAL (t = 4.983, p < 0.001) volumes were all significantly increased in the ESZ group, and the lPUT (t = 3.314, p = 0.002), lPAL (t = 6.334, p < 0.001), and rPAL (t = 3.604, p < 0.001) subregion volumes were also significantly increased in the CSZ group. Correlation analysis showed that lPUT and bilateral globus pallidus were associated with cumulative dose of antipsychotics, but were not associated with clinical symptoms in each subregion. CONCLUSION: The findings suggest that different subregions of the striatum and globus pallidus show significant volume differences at different stages of schizophrenia compared to HC. These volume differences may be strong radiographic evidence for schizophrenia. In addition, the lPAL was the only significantly different brain region observed in the FSZ group, suggesting that it may be a sensitive indicator of early brain structural changes in schizophrenia. Finally, our findings support the hypothesis that antipsychotic drugs have an effect on the volume of brain structures.


Assuntos
Antipsicóticos , Corpo Estriado , Globo Pálido , Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Esquizofrenia/patologia , Esquizofrenia/diagnóstico por imagem , Globo Pálido/diagnóstico por imagem , Globo Pálido/patologia , Masculino , Feminino , Adulto , Estudos Retrospectivos , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/patologia , Adulto Jovem , Antipsicóticos/uso terapêutico , Pessoa de Meia-Idade , Progressão da Doença
5.
Pol J Microbiol ; 72(4): 355-363, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095865

RESUMO

Circadian rhythms influence various aspects of the biology and physiology of the host, such as food intake and sleep/wake cycles. In recent years, an increasing amount of genetic and epidemiological data has shown that the light/dark cycle is the main cue that regulates circadian rhythms. Other factors, including sleep/wake cycles and food intake, have necessary effects on the composition and rhythms of the gut microbiota. Interestingly, the gut microbiota can affect the circadian rhythm of hosts in turn through contact-dependent and contact-independent mechanisms. Furthermore, the gut microbiota has been shown to regulate the sleep/wake cycles through gut-brain-microbiota interaction. In addition to diabetes, the gut microbiota can also intervene in the progression of neuro- degenerative diseases through the gut-brain-microbiota interaction, and also in other diseases such as hypertension and rheumatoid arthritis, where it is thought to have a spare therapeutic potential. Even though fecal microbiota transplantation has good potential for treating many diseases, the risk of spreading intestinal pathogens should not be ignored.


Assuntos
Microbioma Gastrointestinal , Ritmo Circadiano/fisiologia
6.
Front Psychiatry ; 14: 1191170, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547217

RESUMO

Objective: There is considerable debate as to whether the continuum of major psychiatric disorders exists and to what extent the boundaries extend. Converging evidence suggests that alterations in hippocampal volume are a common sign in psychiatric disorders; however, there is still no consensus on the nature and extent of hippocampal atrophy in schizophrenia (SZ), major depressive disorder (MDD) and bipolar disorder (BD). The aim of this study was to verify the continuum of SZ - BD - MDD at the level of hippocampal subfield volume and to compare the volume differences in hippocampal subfields in the continuum. Methods: A total of 412 participants (204 SZ, 98 MDD, and 110 BD) underwent 3 T MRI scans, structured clinical interviews, and clinical scales. We segmented the hippocampal subfields with FreeSurfer 7.1.1 and compared subfields volumes across the three diagnostic groups by controlling for age, gender, education, and intracranial volumes. Results: The results showed a gradual increase in hippocampal subfield volumes from SZ to MDD to BD. Significant volume differences in the total hippocampus and 13 of 26 hippocampal subfields, including CA1, CA3, CA4, GC-ML-DG, molecular layer and the whole hippocampus, bilaterally, and parasubiculum in the right hemisphere, were observed among diagnostic groups. Medication treatment had the most effect on subfields of MDD compared to SZ and BD. Subfield volumes were negatively correlated with illness duration of MDD. Positive correlations were found between subfield volumes and drug dose in SZ and MDD. There was no significant difference in laterality between diagnostic groups. Conclusion: The pattern of hippocampal volume reduction in SZ, MDD and BD suggests that there may be a continuum of the three disorders at the hippocampal level. The hippocampus represents a phenotype that is distinct from traditional diagnostic strategies. Combined with illness duration and drug intervention, it may better reflect shared pathophysiology and mechanisms across psychiatric disorders.

7.
Chem Commun (Camb) ; 59(69): 10330-10342, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615403

RESUMO

DNA walkers, artificial dynamic DNA nanomachines, can mimic actin to move rapidly along a predefined nucleic acid track. They can generally be classified as one- (1D), two- (2D), and three-dimensional (3D) DNA walkers. In particular, 3D DNA walkers demonstrate amazing sustainable walking ability, strong enrichment ability, and fantastic signal amplification ability. In light of these, 3D DNA walkers have been widely used in fields such as biosensors, bioanalysis and cell imaging. Most notably, the strong compatibility of 3D DNA walkers allows their integration with a range of amplification strategies, effectively enhancing signal transduction and amplifying biosensor sensing signals. Herein, we first systematically expound the walking principle of the 3D walkers in this review. Then, by presenting representative examples, the research direction of 3D walkers in recent years is discussed. Furthermore, we also categorize and evaluate diverse tandem signal amplification strategies in 3D walkers. Finally, the challenges and development trends of 3D DNA walkers in the emerging field of analysis are carefully discussed. It is believed that this work can provide new ideas for researchers to quickly understand 3D DNA walkers and their applications in diverse biosensors.


Assuntos
DNA , Ácidos Nucleicos , Actinas , Transdução de Sinais , Tecnologia
8.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36724284

RESUMO

AIM: Combining MALDI-TOF MS and machine learning to establish a new rapid method to identify two important serotypes of Rimerella anatipestifer. METHODS AND RESULTS: MALDI-TOF MS was performed on 115 R. anatipestifer strains (serotype 1, serotype 2, and other serotypes) to explore its ability to identify serotypes of R. anatipestifer. Raw spectral data were generated in diagnostic mode; these data were preprocessed, clustered, and analysed using principal component analysis. The results indicated that MALDI-TOF MS completely differentiated serotype 1 from serotype 2 of R. anatipestifer; the potential serotype-associated m/z loci are listed. Furthermore, Random Forest and Support Vector Machine were used for modelling to identify the two important serotypes, and the results of cross-validation indicated that they had ∼80% confidence to make the right classification. CONCLUSION: We proved that MALDI-TOF MS can differentiate serotype 1 from serotype 2 of R. anatipestifer. Additionally, the identification models established in this study have high confidence to screen out these two important serotypes from other serotypes.


Assuntos
Doenças das Aves Domésticas , Riemerella , Animais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Sorogrupo , Riemerella/genética , Aves , Aprendizado de Máquina
9.
Sci Rep ; 12(1): 19772, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396948

RESUMO

Severe diseases like cirrhosis and liver failure can be developed from primary biliary cholangitis (PBC). Endothelin-2 (EDN2) and endothelin receptor B (EDNRB) are related to the pathogenesis of PBC. However, the roles of EDN2 and EDNRB in PBC-related liver injury and inflammation along with molecular mechanisms are poorly defined. In this study, histopathologic alterations of liver tissues were assessed through hematoxylin-eosin staining. Alanine transaminase (ALT), alkaline phosphatase (ALP), aspartate transaminase (AST), and γ-Glutamyltranspetidase (GGT) (4 liver function indexes) serum levels were detected with corresponding activity assay kits. Also, we determined the levels of M2 subtype anti-mitochondrial antibody (AMA-M2), interferon-gamma (IFN-γ), and tumor-necrosis factor alpha (TNFα) in serum with ELISA assay. Later, RT-qPCR assay was used to measure the expression of genes at mRNA levels, while western blotting and immunohistochemical techniques were used to detect protein levels of genes. Our results showed that the liver tissues of PBC patients and mice presented with severe hepatocyte injury and inflammatory cell infiltration as well as destruction of intrahepatic small bile ducts. ALP, AST, ALT, GGT, AMA-M2, IFN-γ, and TNF-α serum levels were higher in PBC patients and mice. Besides, EDN2 and EDNRB were highly expressed in serums and livers of PBC patients and mice. EDNRB potentiated PBC-related liver injury and pro-inflammatory responses, as evidenced by observation of serious liver pathologic injury and increased serum levels of ALP, AST, ALT, AMA-M2, IFN-γ, and TNF-α in PBC mice following EDNRB overexpression. EDNRB overexpression or activation via its agonist IRL-1620 TFA triggered liver injury and pro-inflammatory responses, increased GRK2 expression and induced NF-κB expression and activation in wild-type mice. EDNRB knockdown or inhibition by Bosentan alleviated liver damage and inflammation, reduced GRK2 expression, and inhibited NF-κB in PBC mice. These findings suggested EDNRB loss or inhibition weakened liver injury and pro-inflammatory responses by down-regulating GRK2 and inhibiting the NF-κB pathway in PBC mice.


Assuntos
Cirrose Hepática Biliar , Animais , Camundongos , Alanina Transaminase , Aspartato Aminotransferases , Inflamação , Interferon gama/metabolismo , Cirrose Hepática Biliar/patologia , NF-kappa B/metabolismo , Receptores de Endotelina , Fator de Necrose Tumoral alfa/metabolismo
10.
Front Psychiatry ; 13: 990660, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159915

RESUMO

Background: There is limited evidence on the efficacy of electroconvulsive therapy (ECT) in adolescents with mental illness. The present study reported outcomes of adolescents with mental illness treated with ECT aimed at providing evidence for large-scale feasibility. Objectives: The primary objective of this trial was to examine the differences in demographic and clinical data between responders and non-responders. The secondary objective was to determine whether ECT produced differential readmission rates, the burden of oral medication, and social function in responders and non-responders in the long term. Methods: Patients aged 14-18 years diagnosed with schizophrenia (SCZ), major depressive disorder (MDD), or bipolar disorder (BD) who received ECT between 2015 and 2020 were included in the study. Demographic and clinical data were compared, and both short-term and long-term outcomes were assessed: response on the Clinical Global Impressions-Improvement scale and readmission at follow-up. The independent-sample t-test was used to compare the continuous variables and the X 2 test was used to compare the dichotomous variables with statistical significance at P ≤ 0.05. Results: Four hundred ten adolescents (aged 14-18 years, 53.90% female) received ECT for SCZ, MDD, and BD. The response rate for SCZ, MDD, and BD were 65.61, 78.57, and 69.95%, respectively. Both SCZ (P = 0.008) and BD (P = 0.008) groups had a significant elder age in responders than in non-responders. Besides that MDD responders had a significantly larger number of ECT sessions than non-responders (P = 0.046), the study failed to find a significant difference in other ECT parameters. A significantly higher proportion of readmission was found in BD non-responders than in responders (P = 0.029), there was no difference in the rate of readmission in other diagnostic groups. Conclusions: These data suggested that ECT is an effective treatment for adolescents with severe mental illness, and the rate of readmission was low in the long term. The present study supports that large-scale systematic studies are warranted for further investigation of the response rate of ECT for treating adolescents with mental illness.

12.
Plant Biotechnol J ; 19(5): 952-965, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33236503

RESUMO

Amphicarpy (seed heteromorphy) is a unique and fascinating reproductive strategy wherein a single plant produces both aerial and subterranean fruits. This strategy is believed to be an adaptation to life under stressful or uncertain environments. Here, we sequenced and de novo assembled a chromosome-level genome assembly of the legume Amphicarpaea edgeworthii Benth. The 299-Mb A. edgeworthii genome encodes 27 899 protein-coding genes and is the most compact sequenced legume genome reported until date. Its reduced genome size may be attributed to the reduced long-terminal repeat retrotransposon content, which stems from the unequal homologous recombination. Gene families related to immunity and stress resistance have been contracted in A. edgeworthii, which is consistent with the notion that the amphicarpic reproductive strategy may be a complementary mechanism for its weak environmental-adaptation ability. We demonstrated the 'ABCE' model for the differentiation of chasmogamous and cleistogamous flowers. In addition, the characteristics of aerial and subterranean seeds in hard-seededness were explored. Thus, we suggest that the A. edgeworthii genome, which is the first of an amphicarpic plant, offers significant insights into its unusual reproductive strategy that is a key resource towards comprehending the evolution of angiosperms.


Assuntos
Fabaceae , Fabaceae/genética , Frutas , Genoma de Planta/genética , Reprodução , Sementes , Verduras
13.
Huan Jing Ke Xue ; 41(3): 1276-1285, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608629

RESUMO

As the source of non-point pollution in the Three Gorges Reservoir Area, small watershed is a key control object in alleviating deterioration of water quality. In the Three Gorges Reservoir Area, the Shipanqiu small watershed with various land-use types was selected as the research object, and the water quantity and quality of the outlet section of the watershed were continuously monitored. We carried out analysis of the small watershed runoff loss and nitrogen and phosphorus pollutants with concentration, analyzed the morphology change characteristics of runoff erosion, calculated the small watershed of pollutant emission flux, and analyzed the nitrogen and phosphorus nutrient loss and main human and natural factors, especially in the Three Gorges Reservoir Area of agriculture where nonpoint source pollution research has important practical significance. The results showed that the rainfall in the watershed varied significantly with the seasons, and the rainfall was mainly distributed from April to June, which was the main output period of nitrogen and phosphorus loss in the small watershed, accounting for 58.94% and 67.60% of the total nitrogen and phosphorus load, respectively, in the whole year. The total annual runoff in the Shipanqiu small watershed was 8.02×104 m3, and the annual total nitrogen loss flux was 5.04 kg·hm-2, of which nitrate nitrogen (2.54 kg·hm-2) was the main part. The total phosphorus output was 0.534 kg·hm-2, and the soluble total phosphorus (0.422kg·hm-2) accounted for 79.00% of the total phosphorus flux. The loss flux of total nitrogen was 9.51 times that of total phosphorus, and the non-point source pollution risk of nitrogen was much greater than that of phosphorus. Therefore, for the Shipanqiu small watershed, it is especially important to prevent nitrogen loss in paddy fields when fertilization and rainfall coincide.

14.
Huan Jing Ke Xue ; 41(4): 1921-1929, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608701

RESUMO

The reduction in chemical fertilizers combined with organic fertilizers is a national strategy to achieve environmental friendliness and maintain the quality of cultivated land. It is of great significance for the prevention and control of soil pollution and the sustainable development of agriculture. In this study, purple soil and sloping land in the Three Gorges Reservoir area was studied. The field experiment method was used to study the control, conventional fertilization, optimized fertilization, biochar (fertilizer combined with biochar), and straw under rapeseed/corn rotation mode. The effects of five treatments on soil nitrogen/phosphorus form, crop nitrogen and phosphorus content, fertilizer utilization rate, and crop yield were studied in the field (fertilizer reduction combined with straw returning). The results showed that the soil ammonium nitrogen content was the highest in the rapeseed season, which was 4.51 mg·kg-1. The contents of ammonium nitrogen and alkali nitrogen in the treated corn season were significantly higher than those in the rape season. The reduction in chemical fertilizers can guarantee and increase the total nitrogen content of the soil. Among them, the total nitrogen content in the rapeseed and corn seasons treated with straw was the highest (0.56 g·kg-1 and 0.60 g·kg-1, respectively). The soil treated with straw in the rapeseed season had the highest available phosphorus content (0.76 mg·kg-1). Compared with conventional treatment, the reduction of chemical fertilizers combined with organic fertilizer did not significantly reduce the total phosphorus content of soil. The reduction of fertilization combined with organic fertilizer showed a slight increase in yield but showed the highest yield of rapeseed treated by biochar (2328 kg·hm-2) and the highest yield of conventionally treated maize (5838 kg·hm-2). However, there was no significant difference in each treatment (P>0.05). Regardless of the rapeseed season or the corn season, the reduction of fertilization treatment generally improved the agronomic utilization rate of nitrogen fertilizer and phosphate fertilizer. In the purple soil area, the combination of chemical fertilizer reduction and biochar and straw returning were beneficial to improve soil nutrients, improve fertilizer utilization, and reduce the effects of nitrogen fertilizer and phosphate fertilizer application on crop yield.

15.
Huan Jing Ke Xue ; 41(4): 1930-1940, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608702

RESUMO

The purple soil sloping field is considered as the main source of sediment and non-point source pollution in the Three Gorges Reservoir area. To prevent and control the non-point source pollution, it is indispensable to explore the characteristics of nitrogen loss in the overland flow and interflow of purple soil sloping field in Three Gorges Reservoir area. The purple soil sloping runoff plots, located in the Shibaozhai Experimental Station of Chengdu Institute of Chinese Academy of Sciences in Zhongxian County, Chongqing, were studied. The experiment included no fertilization treatment (CK), traditional fertilization treatment (T1), amended fertilization treatment (T2), and reduced fertilizer with straw treatment (T3). According to the data of volume of the interflow and runoff and the leach concentration and flux of nitrogen forms under rapeseed-maize rotation system, the response of nitrogen leaching flux to reduce fertilizer with straw application can be definite in purple soil sloping plots. The results show that the ratio of interflow to total runoff is 60.14%-88.56%, and the flux of nitrogen leaching in the interflow accounts for 72.88%-92.35% of total nitrogen loss flux. Ammonium was mainly leached by the overland flow. In addition, nitrate was mainly leached by the interflow and was the main form of nitrogen leaching. The fluxes of ammonium and nitrate under different treatments followed the order T1 > T2 > T3 > CK. The total nitrogen flux of T3 was 20.07 kg·(hm2·a)-1, which was 43.59% and 39.55% lower than that of T1 and T2, respectively. The reduced fertilizer with straw application significantly decreased the leaching flux of ammonium, nitrate, and total nitrogen, and weakened the effect on runoff nitrogen leaching in the purple soil sloping plots.

16.
Huan Jing Ke Xue ; 41(5): 2406-2415, 2020 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608860

RESUMO

This study seeks to clarify the effect of biochar application on nitrogen loss patterns and flux in purple arid sloping land, so as to provide a scientific basis for improving the quality of farmland and reducing the risk of agricultural non-point source pollution in purple arid sloping land. The effects of four treatments on surface runoff and soil nitrogen loss patterns and fluxes in purple arid sloping land were studied by field experiments, including no fertilization (control), conventional fertilization, optimized fertilization, and biochar (fertilizer reduction and biochar application). The results showed that:① Of the fertilization treatments, the total runoff of conventional treatment was the highest at 16133 L·a-1, and the total runoff of biochar treatment was the lowest at 11893 L·a-1. In each fertilization treatment, soil midstream was the main mode of runoff, accounting for 61.80%-68.60% of the total loss. Compared with the control (no fertilization treatment), the sediment loss in other fertilization treatments was decreased, with conventional treatment showing the most significant effect. ② Ammonium nitrogen is mainly lost by surface runoff, accounting for 86.51%-96.58% of the total loss flux. Biochar treatment had the highest loss flux at 0.69 kg·(hm2·a)-1, and the control treatment had the lowest at 0.17 kg·(hm2·a)-1. ③ The concentration of granular nitrogen in the production flow of each fertilization treatment was higher than that of the control treatment, and the loss flux of granular nitrogen in the conventional fertilization treatment was the highest at 2.87 kg·(hm2·a)-1. ④ There was a significant positive correlation between total nitrogen concentration and nitrate nitrogen concentration in the soil midstream and surface runoff of each fertilization treatment (P<0.01). Nitrate nitrogen is the main form of total nitrogen loss, and both take soil midstream as the main way of loss. The total nitrogen loss through soil flow accounted for 72.86%-89.13%, and that of conventional fertilization was the highest at 35.58 kg·(hm2·a)-1, whereas that of biochar treatment was the lowest at 21.49 kg·(hm2·a)-1. Reducing the amount of fertilizer and applying biochar can significantly reduce the runoff and nitrogen flux, and effectively prevent and control the risk of agricultural non-point source pollution.

17.
Microb Pathog ; 142: 104044, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32032766

RESUMO

Bacterial non-coding RNAs (ncRNAs) can participate in multiple biological processes, including motility, biofilm formation, and virulence. Using high-throughput sequencing and transcriptome analysis of Salmonella enterica serovar Typhi (S. Typhi), we identified a novel antisense RNA located at the opposite strand of the flhDC operon. In this study, a northern blot and qRT-PCR were used to confirm the expression of this newfound antisense RNA in S. Typhi. Moreover, 5' RACE and 3' RT-PCR were performed to reveal the molecular characteristics of the antisense RNA, which was 2079 nt - 2179 nt in length, covered the entire flhDC operon sequence, and termed AsfD. The level of AsfD expression was higher during the stationary phase of S. Typhi and activated by the regulators, OmpR and Fis. When AsfD was overexpressed, the level of flagellar gene flhDC transcription increased; moreover, the level of fliA and fljB expression, as well as the motility and biofilm formation of S. Typhi were also enhanced. The results of this study suggest that AsfD is likely to enhance the motility and biofilm formation of S. Typhi by up-regulating flhDC expression.

18.
FEBS Open Bio ; 10(6): 1013-1020, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32069380

RESUMO

Growth hormone receptor (GHR), a member of the class I cytokine receptor family, plays key roles in cancer progression. Recently, GHR has been reported to be associated with breast cancer development, but the molecular mechanism of GHR in this malignancy is not fully understood. To investigate this issue, we stably inhibited GHR in breast cancer cell lines, which were observed to reduce cell proliferation, tumor growth and induction of apoptosis, and arrest the cell-cycle arrest at the G1-S phase transition. In addition, GHR silencing suppressed the protein levels of B-Raf proto-oncogene, serine/threonine kinase (BRAF), Mitogen-activated protein kinase kinase (MEK) and Extracellular regulated protein kinases (ERK). These findings suggest that GHR may mediate breast cell progression and apoptosis through control of the cell cycle via the BRAF/MEK/ERK signaling pathway.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Transporte/metabolismo , Animais , Apoptose , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/cirurgia , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Mastectomia , Camundongos , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas B-raf/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Plant Sci ; 287: 110199, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481201

RESUMO

Eutrema salsugineum is considered as extremophile model species. To gain insights into the root hydraulic conductivity and the role played by aquaporins in E. salsugineum, we investigated the aquaporin family profiles, plant water status and root hydraulic conductivity under standard (salt-free) and salt stress conditions. We found that there was no variation in the relative electric conductivity of the leaves when the salt concentration was less than 200 mM NaCl, and the transpiration rate dropped to 60.6% at 100 mM NaCl for 14 days compared to that at standard conditions. The pressure chamber techniques indicated that the root hydraulic conductivity of E. salsugineum was repressed by salt stress. However, propionic acid, usually used as an aquaporin inhibitor, unexpectedly enhanced the root hydraulic conductivity of E. salsugineum. The aquaporin family in E. salsugineum was profiled and the PIP aquaporin expression was investigated at the transcriptional and translational levels. Finally, two EsPIPs were identified to play a role in salt stress. The overall study provides evidence on how halophytes maintain their water status and aquaporin regulation pattern under salt stress conditions.


Assuntos
Aquaporinas/metabolismo , Brassicaceae/fisiologia , Regulação da Expressão Gênica de Plantas , Aquaporinas/genética , Transporte Biológico , Brassicaceae/genética , Filogenia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Transpiração Vegetal , Estresse Salino , Tolerância ao Sal , Plantas Tolerantes a Sal , Estresse Fisiológico , Água/metabolismo
20.
Huan Jing Ke Xue ; 40(1): 401-411, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628299

RESUMO

Crop straw is an important agricultural source, which can replace chemical fertilizers. A field experiment with six different amounts of fertilization combined with maize straw residues was carried out in purple soil, including the control (CK), conventional fertilizing (F), straw return with conventional fertilizing (100FS), straw return with 70% conventional fertilizing (70FS), straw return with 60% conventional fertilizing (60FS), and straw return with 50% regular fertilizing (50FS), to determine the response of the soil N2O emission and ammonia-oxidizing microorganism community distribution to straw return with reducing fertilizer. The dynamic characteristics of the N2O emission in purple soil were observed using an in situ closed chamber and gas chromatography-based system. The ammonia-oxidizing microorganism community distribution was analyzed with multiple molecular techniques (DNA-based clone library and qPCR) linked to physical-chemical soil properties. The results show that the combination of straw with fertilizer increases the N2O emission and cumulative N2O emission. The highest N2O emission[57.59-6238.02 µg·(m2·h)-1]and cumulative N2O emission (60.76 kg·hm-2) were observed for the 100FS treatment. Compared with the F treatment, the soil ammonium nitrogen and nitrate nitrogen contents are reduced and the soil organic matter increases after crop straw return with chemical fertilizer. However, significant changes of the soil total nitrogen and pH were not observed. The bacterial ammonia oxidizer (AOB) amoA gene abundance is higher than that of the archaeal ammonia oxidizer (AOA). The AOA amoA gene abundance during F treatment (50.9×103 copies·g-1) is significantly higher than that of others, while the AOB amoA abundance gene of the F treatment is the lowest (1.36×105 copies·g-1). The 100FS reduces the community diversity and Pielou index of AOA and AOB amoA gene. Their amoA gene abundance significantly declines during 100FS treatment. However, the increment of the AOA and AOB amoA gene diversity and dominant increment of AOB amoA gene abundance are significant when applying straw with reducing fertilizer. The specific AOA indicator OTU1 may be most important with respect to the direct and indirect production of N2O in purple soil. The redundancy analysis (RDA) shows that the community structure of AOA is remarkably relevant to the soil ammonium nitrogen, organic matter, and available phosphorus (P<0.05) and that the community structure of AOB is remarkably relevant to the soil dissolved organic nitrogen, total nitrogen, available potassium, and available phosphorus (P<0.05). The tolerance to different environments and ecological niches of AOB is weaker than that of AOA. Our results illustrate that the maize straw return with 60%-70% regular fertilizing dramatically increases the community diversity and abundance of the AOA and AOB amoA genes and partly mitigates the soil N2O emission without significantly decreasing the vegetable yields.


Assuntos
Amônia/metabolismo , Fertilizantes , Óxido Nitroso/análise , Microbiologia do Solo , Archaea , Bactérias , Genes Arqueais , Genes Bacterianos , Oxirredução , Filogenia , Caules de Planta , Solo/química , Zea mays
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